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Systematizing Teacher Development:A Review of Foreign Language Teacher Learning
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作者 Guang ZENG 《Chinese Journal of Applied Linguistics》 2024年第3期518-523,526,共7页
Foreign language teaching practice is developing rapidly,but research on foreign language teacher learning is currently relatively fragmented and unstructured.The book Foreign Language Teacher Learning,written by Prof... Foreign language teaching practice is developing rapidly,but research on foreign language teacher learning is currently relatively fragmented and unstructured.The book Foreign Language Teacher Learning,written by Professor Kang Yan from Capital Normal University,published in September 2022,makes a systematic introduction to foreign language teacher learning,which to some extent makes up for this shortcoming.Her book presents the lineage of foreign language teacher learning research at home and abroad,analyzes both theoretical and practical aspects,reviews the cuttingedge research results,and foresees the future development trend,painting a complete research picture for researchers in the field of foreign language teaching and teacher education as well as front-line teachers interested in foreign language teacher learning.This is an important inspiration for conducting foreign language teacher learning research in the future.And this paper makes a review of the book from aspects such as its content,major characteristics,contributions and limitations. 展开更多
关键词 foreign language teacher learning foreign language teacher education foreign language teaching teacher development
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Colonoscopy-assisted removal of an impaction foreign body at the rectosigmoid junction: A case report
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作者 Peng-Fei Zhou Jin-Gen Lu +1 位作者 Jia-Dong Zhang Jia-Wen Wang 《World Journal of Clinical Cases》 SCIE 2024年第11期1990-1995,共6页
BACKGROUND When an anorectal foreign body is found,its composition and shape should be evaluated,and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious compl... BACKGROUND When an anorectal foreign body is found,its composition and shape should be evaluated,and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious complications such as intestinal perforation caused by displacement of the foreign body.CASE SUMMARY A 54-year-old male was admitted to our outpatient clinic on June 3,2023,due to a rectal foreign body that had been embedded for more than 24 h.The patient reported using a glass electrode tube to assist in the recovery of prolapsed hemorrhoids,however,the electrode tube was inadvertently inserted into the anus and could not be removed by the patient.During hospitalization,the patient underwent surgery,and the foreign body was dragged into the rectum with the aid of colonoscopy.The anus was dilated with a comb-type pulling hook and an anal fistula pulling hook to widen the anus and remove the foreign body,and the local anal symptoms were then relieved with topical drugs.The patient was allowed to eat and drink,and an entire abdominal Computed tomography(CT)and colonoscopy were reviewed 3 d after surgery.CT revealed no foreign body residue and colonoscopy showed no metal or other residues in the colon and rectum,and no apparent intestinal tract damage.CONCLUSION The timeliness and rationality of the surgical and therapeutic options for this patient were based on a literature review of the clinical signs and conceivable conditions in such cases.The type,material and the potential risks of rectal foreign bodies should be considered. 展开更多
关键词 foreign body impaction Surgical therapy Rectum-sigmoid colon COLONOSCOPY Case report
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Wang Yi Addresses Symposium on International Situation and China's Foreign Relations in 2023
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《China International Studies》 2024年第1期F0002-F0002,共1页
On January 9,2024,the Symposium on the International Situation and China’s Foreign Relations in 2023 was held in Beijing.Member of the Political Bureau of the CPC Central Committee and Foreign Minister Wang Yi attend... On January 9,2024,the Symposium on the International Situation and China’s Foreign Relations in 2023 was held in Beijing.Member of the Political Bureau of the CPC Central Committee and Foreign Minister Wang Yi attended the symposium and delivered a keynote speech entitled“Self-Confidence and SelfReliance,Openness and Inclusiveness,Fairness and Justice,and Win-Win Cooperation.” 展开更多
关键词 CONFIDENCE foreign entitled
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Management of Vulnating Esophageal Foreign Bodies in Burkina Faso
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作者 Ibrahima Diallo Aboubacar Gouéta +8 位作者 Alseny Camara Assoumi Anatou Biga Mama Brigitte Ouoba Edi Emmanuel Martial Nao Moustapha Sérémé Bertin Priva Ouédraogo Yvette Marie Chantal Gyébré Abdoulaye Keita Alpha Oumar Diallo 《International Journal of Otolaryngology and Head & Neck Surgery》 2024年第2期135-148,共14页
Introduction: Esophageal foreign bodies (EFB) are a diagnostic and therapeutic emergency because of the serious complications they can cause. Aim: This paper aimed to study the vulnating esophageal foreign bodies in t... Introduction: Esophageal foreign bodies (EFB) are a diagnostic and therapeutic emergency because of the serious complications they can cause. Aim: This paper aimed to study the vulnating esophageal foreign bodies in the ENT and Head and Neck Surgery departments of the Yalgado Ouedraogo and Bogodogo University Hospital. Methodology: This was an analytic cross-sectional study with retrospective data collection over 10 years (2012-2021). Results: We collected 91 cases of vulnating esophageal foreign bodies, i.e. 9.1 cases/year (4.7%). The mean age of the patients was 14 ± 19 years. The sex ratio was 1.6. The circumstances of occurrence were dominated by accidental ingestion of vulnating esophageal foreign bodies (98.9%). The average time to consultation was 7.5 hours. Dysphagia was the dominant symptom (64.8%). Cervico-thoracic radiography found dual contour radiopaque images in 71.4%. Esophagoscopy with rigid tube was performed in 97.8%. The average time for extraction of the vulnating esophageal foreign bodies was 8 hours. Vulnerating esophageal foreign bodies were non-organic in 84.6%. The button cell represented 64.8%. Their location was cervical in 61.5% intraoperatively. The lesion assessment found ulcerative lesions in 42.9% (p Conclusion: Vulnating esophageal foreign bodies are relatively frequent in our ENT practice. Although their diagnosis is often easy, their treatment is still difficult and requires multidisciplinary management. Thus, for us, prevention remains the first effective weapon. 展开更多
关键词 foreign Bodies ESOPHAGUS VULNERABLE mANAGEmENT SEQUELAE
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Let’s Talk LGBTQIA+:Strategies and Activities for Teaching Diversity and Inclusion in the Foreign Language Classroom at the College Level
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作者 Joseph Abraham Levi 《Sino-US English Teaching》 2024年第4期143-170,共28页
In this presentation,the author explores strategies and activities that create a welcoming and nurturing environment for LGBTQIA+foreign language students at the college level in the United States.Indeed,as it is comm... In this presentation,the author explores strategies and activities that create a welcoming and nurturing environment for LGBTQIA+foreign language students at the college level in the United States.Indeed,as it is commonly stated,there is a clear lack of visibility,acceptance/tolerance,and inclusion of LGBTQIA+voices(active and proactive)in foreign language teaching and learning(pedagogical material as well as in-class attitudes and delivery).The reasons for this deficiency are diverse since they cover not only outward discrimination against and/or indifference(passive-aggressive behavior)toward the LGBTQIA+community and its plight,but they also illustrate the sheer,physical inexistence of quality material that can be used to create,present,and foster a welcoming and all-encompassing classroom environment that addresses the diverse spectrum of the LGBTQIA+community while its members try to learn a foreign language and(positively)negotiate how to express their very identity in their new language of choice.Moreover,the scant material that is available in the United States as well as in other Western countries where the LGBTQIA+community by and large is accepted-at least from the legal point of view-hardly represents and covers the subject matter in a satisfactory way.To address this gap,the author will provide some examples in European Portuguese(EP)and Italian(IT),followed by a courtesy translation in English,to illustrate some positive activities and strategies for including LGBTQIA+-related subject matter in the foreign language classroom at the college level.It is his desire that instructors of other foreign languages duplicate in their respective vernaculars the strategies and activities herein presented in order to create a welcoming and safe classroom environment that embraces the LGBTQIA+community as it goes through the enjoyable journey of learning a new language and culture. 展开更多
关键词 DIVERSITY foreign language (trans-)gender INCLUSION LGBTQIA+community
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An Empirical Study on Students’Evaluation of Moral Education in Foreign Language Education in China
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作者 LI Yue’e LI Ling 《Journal of Literature and Art Studies》 2024年第8期718-721,共4页
Students’evaluation of moral education is of great significance for improving the quality of teaching.Through a survey of 2715 undergraduates majoring in foreign languages,this paper analyzes their evaluation of the ... Students’evaluation of moral education is of great significance for improving the quality of teaching.Through a survey of 2715 undergraduates majoring in foreign languages,this paper analyzes their evaluation of the moral education.Findings show that students speak highly of teachers’competence in moral education,teaching methods and the integration of moral education in the textbooks,but not in the course assessment and the overall effect of moral education.Suggestions were proposed accordingly to improve moral education of foreign language education in China. 展开更多
关键词 curriculum moral education students’evaluate of teaching foreign language education
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Inspired by Innovation China’s hi-tech achievements add to its appeal for foreign investors
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作者 XIA YUANYUAN 《ChinAfrica》 2024年第5期46-47,共2页
China’s focus on nurturing new quality productive forces while promoting high-quality development provides foreign investors with enormous market opportunities and vast development prospects,amid rising uncertainties... China’s focus on nurturing new quality productive forces while promoting high-quality development provides foreign investors with enormous market opportunities and vast development prospects,amid rising uncertainties in the global economic landscape.In a series of recent engagements with China,foreign investors,including British businesses,have expressed confidence in the future prospects of the market. 展开更多
关键词 INVESTOR foreign productive
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The Application of the Domestication and Foreignization Translation Strategies in the Context of the Dissemination of Chinese Culture:A Case Study of the English Translation of Long
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作者 Xueming Li 《Journal of Educational Theory and Management》 2024年第2期16-19,共4页
In January 2024,the Chinese Year of the Loong,how to translate the Chinese character Long went viral on the Internet.Taking the English translation of Long as an example,this study tends to make a tentative analysis o... In January 2024,the Chinese Year of the Loong,how to translate the Chinese character Long went viral on the Internet.Taking the English translation of Long as an example,this study tends to make a tentative analysis of the application of translation strategies in the macro context of the dissemination of Chinese culture.Moreover,it probes into the phenomenon of Chinese cultural aphasia by analyzing the domestication and foreignization of Long in three aspects.The three attitudes provided ought to be addressed in the Chinese-English translations.This study emphasizes enhancing translators’cultural awareness and their cultural confidence in the process of translating the source language to the target language. 展开更多
关键词 DOmESTICATION foreignIZATION Chinese Culture Cultural Confidence
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Research Nexus and Implications of Learner Identity in Foreign Language Education
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作者 Tenglong Gong 《Journal of Contemporary Educational Research》 2024年第2期48-56,共9页
One of the most obvious markers of an individual’s identity is their language.However,in some ways,the relationship between identity and language acquisition seems to be missed.In fact,a lot of studies have shown tha... One of the most obvious markers of an individual’s identity is their language.However,in some ways,the relationship between identity and language acquisition seems to be missed.In fact,a lot of studies have shown that identity may influence the reasons behind language acquisition,especially in bilingual or multilingual societies.Learning English can provide EFL(English as a Foreign Language)students with a good sense of identity and encourage them to practice their agency,which can improve learning efficiency and effectiveness.This paper examines how the efficacy and results of language learning are influenced by the learner’s identity. 展开更多
关键词 Learner identity mOTIVATION English learning foreign language education
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Research on Foreign Language Talent Cultivation Mode Based on the Concept of Language Security
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作者 Ying Qin 《Journal of Contemporary Educational Research》 2024年第4期150-156,共7页
Language security is an important part of national security,and in the current complex international environment,the issue of language security is becoming more and more prominent and has become an unignorable part of... Language security is an important part of national security,and in the current complex international environment,the issue of language security is becoming more and more prominent and has become an unignorable part of national security strategy.As the bridge and link of international communication,foreign language talents’language skills and the level of national security awareness directly affect our country’s international image and the effect of international communication.Therefore,the establishment of a foreign language talent cultivation mode based on the concept of language security is not only an important way to improve the quality of foreign language education but also a realistic need to safeguard national security and promote international exchanges.Starting from the influence of the language security concept on foreign language talent cultivation,this paper analyzes the foreign language talent cultivation mode based on the language security concept,with a view to providing new ideas and methods for the development of foreign language education. 展开更多
关键词 Language security foreign language talents Cultivation mode
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Combined laparoscopic and endoscopic method for foreign body removal from descending colon: A case report
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作者 Khairunnisa Che Ghazali Huzairi Yaacob Ahmad Shanwani Mohamed Sidek 《World Journal of Surgical Procedures》 2024年第1期1-7,共7页
BACKGROUND The majority of published reports on foreign bodies(FBs)involve the rectum and applied a transanal retrieval.Usually,patients with FB above the rectum are subjected to laparotomy for removal.Here,we illustr... BACKGROUND The majority of published reports on foreign bodies(FBs)involve the rectum and applied a transanal retrieval.Usually,patients with FB above the rectum are subjected to laparotomy for removal.Here,we illustrate the case of a man with an FB that had migrated into the descending colon,and its successful removal via a laparoscopic approach.CASE SUMMARY A 43-year-old man,who had the habit of FB insertion into his anus to aid defe-cation,presented upon experience of such an FB slipping through and migrating upward to the distal colon.Plain abdominal radiograph revealed a bottle-shaped FB,positioned in the left iliac fossa region.The FB was successfully removed via a laparoscopic-assisted procedure in which we combined diagnostic laparoscopic and endoscopic techniques during surgery.The patient was monitored for 2 d postoperatively and subsequently discharged home.CONCLUSION A minimally invasive approach should be adopted to aid extraction of colorectal FB as it is effective and safe. 展开更多
关键词 foreign body COLORECTAL Laparoscopic approach Removal technique minimally invasive Case report
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Research on the Status Quo and Improvement Needs of Foreign Language Teachers’ Teaching Competence in Curriculum-Based Ideological Education in Xinjiang Colleges and Universities
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作者 Xiaoling Liu 《Journal of Contemporary Educational Research》 2024年第3期101-110,共10页
This study investigated the status quo and further improvement needs of foreign language teachers’teaching competence in curriculum-based ideological education(CIE)in Xinjiang colleges and universities.The results sh... This study investigated the status quo and further improvement needs of foreign language teachers’teaching competence in curriculum-based ideological education(CIE)in Xinjiang colleges and universities.The results show that the teachers’teaching competence in CIE is generally good,with the“cultivating quality”being the highest and the“scientific research quality”the lowest;there still exist several problems,such as teachers’lack of theoretical knowledge in CIE,lack of teaching resources,and insufficient abilities in teaching design and research.It is hoped that with the support and efforts from university administrations,teachers can improve their teaching competence in CIE through various approaches adopted and multiple measures taken,thus optimizing their teaching effectiveness,promoting the construction of CIE in Xinjiang colleges and universities in the new era,and contributing to Xinjiang’s high-quality development. 展开更多
关键词 foreign language teachers Curriculum-based ideological education Teaching competence Status quo Improvement needs
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过表达lncRNAHEM2M改善非酒精性脂肪肝病小鼠的肝脏损伤 被引量:1
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作者 孔祥 张腾 +5 位作者 张妍 高灵犀 汪文 汪梦燕 王国栋 吕坤 《南方医科大学学报》 CAS CSCD 北大核心 2024年第1期1-8,共8页
目的探讨过表达长链非编码RNA(lncRNA)HEM2M对非酒精性脂肪肝病(NAFLD)小鼠肝损伤的影响。方法野生型C57BL/6(WT)和条件性髓系细胞lncRNAHEM2M过表达(MYKI)小鼠分别喂饲普通饮食(ND)和高脂饮食(HFD),即为WT+ND、MYKI+ND、WT+HFD和MYKI+... 目的探讨过表达长链非编码RNA(lncRNA)HEM2M对非酒精性脂肪肝病(NAFLD)小鼠肝损伤的影响。方法野生型C57BL/6(WT)和条件性髓系细胞lncRNAHEM2M过表达(MYKI)小鼠分别喂饲普通饮食(ND)和高脂饮食(HFD),即为WT+ND、MYKI+ND、WT+HFD和MYKI+HFD组。12周后行腹腔糖耐量及胰岛素耐量试验后处死小鼠,检测小鼠血清和肝脏组织的肝功能指标,制备肝脏组织切片后行HE染色和F4/80免疫组化染色,ELISA法检测肝脏组织中IL-6、IL-1β和TNF-α水平,qRT-PCR检测M1型(TNF-α、iNOS和IL-6)和M2型(Arg-1、YM-1和IL-10)巨噬细胞标志物mRNA表达,免疫印迹检测肝脏组织中P-AKT、T-AKT、NLRC4、caspase-1和GSDMD蛋白表达,比色法和免疫荧光测定肝脏组织caspase-1活性。结果与HFD喂饲的WT小鼠相比,MYKI+HFD小鼠肝功能损伤减轻(P<0.01),肝脏脂肪变缓解,肝脏巨噬细胞浸润减少,糖耐量损伤及胰岛素抵抗改善(P<0.01);MYKI+HFD小鼠肝脏组织IL-6、IL-1β和TNF-α水平降低(P<0.01),M1型巨噬细胞标志物mRNA表达减少(P<0.01),M2型mRNA表达增加(P<0.01);MYKI+HFD小鼠肝脏组织NLRC4炎症小体活性降低(P<0.01),活性caspase-1减少,GSDMD-N蛋白表达降低(P<0.05)。结论过表达lncRNAHEM2M降低NAFLD小鼠肝脏炎症因子水平,进而改善胰岛素抵抗并抑制肝脏NLRC4炎症小体激活,减少肝细胞焦亡,最终改善NAFLD小鼠肝脏损伤。 展开更多
关键词 lncRNAHEm2m 巨噬细胞 非酒精性脂肪肝 细胞焦亡
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下调METTL5通过Wnt/β-catenin信号通路抑制三阴乳腺癌细胞增殖、迁移与侵袭 被引量:1
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作者 吴坤琳 严乾壹 +2 位作者 王德星 缪秀英 张惠灏 《中国药理学通报》 CAS CSCD 北大核心 2024年第2期285-291,共7页
目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的s... 目的探讨甲基转移酶5(methyltransferase-like 5,METTL5)在三阴乳腺癌(triple-negative breast cancer,TNBC)中的作用和潜在机制。方法采用免疫组织化学方法和Western blot检测TNBC肿瘤组织和细胞系中METTL5的表达情况。用靶向METTL5的shRNA(shRNA-METTL5)转染TNBC细胞后,用CCK-8、集落形成、伤口愈合以及Transwell实验分别检测细胞增殖活性、迁移与侵袭,Western blot检测Wnt/β-catenin信号关键蛋白的表达。构建异种移植瘤模型,验证敲降METTL5对TNBC细胞在体内生长以及Wnt/β-catenin信号活性的影响。结果METTL5在TNBC肿瘤组织和细胞系中表达上调(P<0.01)。敲降METTL5可抑制TNBC细胞的增殖、迁移和侵袭并降低了Wnt/β-catenin信号分子β-catenin、细胞周期蛋白(Cyclin)D1、基质金属蛋白酶(MMP)-2和MMP-7的表达(均P<0.01)。体内实验显示,敲降METTL5减缓了移植瘤生长和Wnt/β-catenin信号活性。结论敲降METTL5能抑制TNBC细胞的增殖、迁移与侵袭,其作用可能与抑制Wnt/β-catenin信号通路有关。 展开更多
关键词 三阴乳腺癌 甲基转移酶5 m6A甲基化 WNT/Β-CATENIN 增殖 迁移 侵袭
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关于7.63m焦炉上升管结石墨原因分析及治理对策的研究
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作者 马素娟 冯敏超 +2 位作者 万文 关晓光 马素霞 《燃料与化工》 CAS 2024年第1期32-34,共3页
德国伍德公司开发的7.63 m特大型复热式焦炉在生产过程中上升管根部结石墨严重,成为制约焦炉正常生产的突出矛盾。从焦炉加热水平、焦炉加热制度、装煤量等因素综合分析影响上升管根部结石墨的成因,研究制定降低上升管根部结石墨速率的... 德国伍德公司开发的7.63 m特大型复热式焦炉在生产过程中上升管根部结石墨严重,成为制约焦炉正常生产的突出矛盾。从焦炉加热水平、焦炉加热制度、装煤量等因素综合分析影响上升管根部结石墨的成因,研究制定降低上升管根部结石墨速率的方法及自动清除上升管根部石墨的装置,达到避免因上升管根部结石墨影响焦炉生产的目的。 展开更多
关键词 7.63 m焦炉 石墨 原因分析 上升管
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基于m×2正则化交叉验证的神经网络超参数调优方法
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作者 曹学飞 杨帆 +2 位作者 李济洪 王瑞波 牛倩 《计算机技术与发展》 2024年第4期168-173,共6页
超参数调优是神经网络建模的关键问题。针对传统的超参数调优方法存在的问题,该文提出了一种基于m×2正则化交叉验证的超参数调优方法。目的是给出一种适用于复杂模型、大数据集背景下的计算开销较小且稳健的超参数调优方法。该方... 超参数调优是神经网络建模的关键问题。针对传统的超参数调优方法存在的问题,该文提出了一种基于m×2正则化交叉验证的超参数调优方法。目的是给出一种适用于复杂模型、大数据集背景下的计算开销较小且稳健的超参数调优方法。该方法的思想是从完整的数据集上选取少部分数据进行调优,避免模型在数据集较大时非常耗时的超参数调优难题;在m×2交叉验证的基础上设置正则化条件均衡训练集与验证集之间的分布差异,从而减少分布不一致带来的性能波动;使用信噪比作为调优的优化目标,从而可以综合考虑模型性能评价指标的均值和方差;并采用正交设计选择相关性较低的超参数组合以提高调优效率。以命名实体任务为例进行实验,在CoNLL 2003数据集上的实验结果显示,提出的调优方法能够选到和网格搜索性能上没有显著差异的超参数组合,且调优时间可显著降低约66%。 展开更多
关键词 m×2交叉验证 正则化 神经网络 超参数调优 信噪比
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高速铁路主跨320 m钢-混部分斜拉桥无砟轨道适应性研究
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作者 王俊冬 欧阳辉来 +2 位作者 魏周春 苏成光 高天赐 《铁道标准设计》 北大核心 2024年第5期29-35,共7页
南玉高铁六景郁江特大桥设计将钢-混部分斜拉桥结构引入时速350 km高速铁路领域,而300 m级以上大跨度桥上无砟轨道的竖向变形极易超限,影响列车通过的安全性和舒适性,因此,系统研究在此大跨桥梁结构上铺设无砟轨道的适应性十分必要。通... 南玉高铁六景郁江特大桥设计将钢-混部分斜拉桥结构引入时速350 km高速铁路领域,而300 m级以上大跨度桥上无砟轨道的竖向变形极易超限,影响列车通过的安全性和舒适性,因此,系统研究在此大跨桥梁结构上铺设无砟轨道的适应性十分必要。通过建立有限元及动力学模型,分析不同组合工况下无砟轨道结构的变形特点及动力特性,运用60 m弦测法探究各工况下无砟轨道的线形变化规律,从而确定大跨度钢-混部分斜拉桥铺设无砟轨道的适应性,并对设计和施工提出合理化建议。主要结论如下:在各种不利组合荷载作用下,桥上无砟轨道结构强度满足规范要求,列车通过大桥的各项安全性与舒适性指标均满足规范要求;混凝土收缩徐变和斜拉索升降温是影响无砟轨道线形标准的两大主因,应在无砟轨道施工前确保足够的沉降观测期和收缩徐变释放期,并充分考虑拉索的保温设计;在温度组合荷载作用下,桥上无砟轨道的60 m弦测不平顺幅值为6.79 mm,满足高速铁路静态验收标准;但在叠加列车荷载和收缩徐变后,变形弦测值均出现Ⅱ级及以上超限,通过合理设置预拱度后可有效改善轨道平顺性标准。 展开更多
关键词 高速铁路 铁路桥 钢-混部分斜拉桥 无砟轨道 车-轨-桥耦合 60 m弦测法 轨道不平顺
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基于GNSS的2023年2月23日塔吉克斯坦M_(S)7.2地震前异常资料变化特征研究
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作者 李桂荣 李杰 +2 位作者 李瑞 苏力坦·玉散 李思妍 《内陆地震》 2024年第1期34-41,共8页
为了进一步探究中强地震发生前GNSS坐标时序中是否存在中短期异常现象,通过分析2023年2月23日塔吉克斯坦M_(S)7.2地震前后中国大陆构造环境监测网络(简称:“陆态网络”)塔什库尔干、布伦口GNSS基准站观测资料的变化特征,发现该地震震前... 为了进一步探究中强地震发生前GNSS坐标时序中是否存在中短期异常现象,通过分析2023年2月23日塔吉克斯坦M_(S)7.2地震前后中国大陆构造环境监测网络(简称:“陆态网络”)塔什库尔干、布伦口GNSS基准站观测资料的变化特征,发现该地震震前塔什库尔干、布伦口均出现较为明显的GNSS基准站时间序列异常现象,震前EW向存在趋势性W向运动,震后E向加速;震前NS向趋势性S向运动,临震前状态快速改变,布伦口在震后还显示出7.3 mm的EW向永久性形变,研究结果表明GNSS在地震发生短临阶段具有重要的预测意义。与2015年12月7日塔吉克斯坦M S7.4地震进行对比发现,两次M S≥7.0地震对塔什库尔干、布伦口基准站的影响差异较大。2015年12月7日塔吉克斯坦M S7.4地震为左旋走滑,影响方向主要为NE向,而2023年2月23日塔吉克斯坦M_(S)7.2地震为右旋走滑,影响方向主要为SE向。震前基线均有挤压缩短的前兆异常显示。梳理站点异常出现情况,发现异常持续时间越长、异常出现次数越多,发震震级可能越大。 展开更多
关键词 GNSS 变化量 塔吉克斯坦m S7.2地震 地震异常
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M-APSK鉴相算法与并行载波同步方法
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作者 郇浩 任科学 《通信学报》 EI CSCD 北大核心 2024年第3期104-116,共13页
为实现M进制幅相调制(M-APSK)体制下高阶调制信号的相位精细校正,将DVB-S2标准推荐的16APSK和32APSK的Q次方无数据辅助鉴相算法进行了扩展,以应用于64APSK、128APSK和256APSK等高阶调制。针对高阶调制的有效鉴相星座点占比较低时环路工... 为实现M进制幅相调制(M-APSK)体制下高阶调制信号的相位精细校正,将DVB-S2标准推荐的16APSK和32APSK的Q次方无数据辅助鉴相算法进行了扩展,以应用于64APSK、128APSK和256APSK等高阶调制。针对高阶调制的有效鉴相星座点占比较低时环路工作不稳定的问题提出了改进算法,通过对功率归一化后接收符号的幅值进行阈值判决,仅在高于阈值时进行鉴相,低于阈值时则不改变滤波器状态和相位补偿值,以提高星座点的鉴相有效性和可靠性,从而降低入锁门限。针对高速数传的符号速率非常高,而处理器的工作时钟频率相对较低的问题,提出了一种适用于M-APSK的并行载波同步方法,可以满足接收机工作时钟处理需要。相对于传统固定编码调制(CCM)的载波同步环路,该并行方法还可应用于可变编码调制(VCM)体制的频率跟踪。 展开更多
关键词 m进制幅相调制 鉴相 并行 载波同步
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2023年12月18日甘肃积石山M 6.2地震的前兆异常和孕震过程
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作者 许健生 李丽 +5 位作者 张瑜 闫万生 杨晓鹏 武银 陈双贵 陈雪梅 《地震工程学报》 CSCD 北大核心 2024年第4期857-866,共10页
为了寻找确切的地震前兆异常,在2023年12月18日甘肃积石山M 6.2地震后,对甘肃省临夏地震台观测资料进行分析,发现临夏台所处地块从2023年1月10日起就处在构造应力的作用下,地块内裂隙张开,吸纳空气,导致钻孔与地面气压差ΔP负异常;从2... 为了寻找确切的地震前兆异常,在2023年12月18日甘肃积石山M 6.2地震后,对甘肃省临夏地震台观测资料进行分析,发现临夏台所处地块从2023年1月10日起就处在构造应力的作用下,地块内裂隙张开,吸纳空气,导致钻孔与地面气压差ΔP负异常;从2月22日起,自然电位差ΔV和单极电阻率ρK相继出现异常变化;从3月16日起,开始了小幅度的预滑活动Xpo,并于8月11日前后达到峰值Xpm。预滑活动使临夏台所处地块内多个小裂隙快速张开,并吸纳气体,导致钻孔气压在12月6日起出现多个负气压脉冲G P,这些异常现象直到震后才结束。震前十几个小时的临震预滑活动使得积聚在孕震断层上的应力进一步加大,克服了断层面上的摩擦力,导致孕震断层失稳破裂,发生了积石山M 6.2地震。鉴于观测到的预滑活动和前兆异常发生的时间、空间都与积石山M 6.2地震有较好的相关性,推测临夏台震前观测到的地块预滑活动、气压差变化、气压脉冲、自然电位差和单极电阻率变化可能是M 6.2地震的前兆异常。前兆异常时空演化过程表明,积石山M 6.2地震的孕震过程分4个阶段。因此,关注震前地块预滑活动和各类前兆异常,对预测未来破坏性地震和研究孕震过程有一定的前兆意义。 展开更多
关键词 预滑活动 气压差ΔP 气压脉冲G P 地震前兆异常 孕震过程 甘肃积石山m 6.2地震
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