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交互式数字叙事:加拿大Writing New Body Worlds阅读治疗新探索
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作者 牟晓青 于志涛 《图书馆论坛》 北大核心 2024年第4期222-230,F0003,共10页
文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性... 文章基于相关研究文献与语料,对加拿大WNB阅读治疗实践进行梳理与归纳。WNB首次使用交互式数字叙事技术,构建面向公众的阅读治疗平台,以其交互式特征,融合了阅读和治疗引导两个过程,提供可访问的非临床方式,可面向大规模人群实现预防性健康干预。基于数据与计算的精准化阅读治疗是数字人文视角下的新变革,更具推广应用价值;以在线阅读平台建设为依托,推进实施平台化的阅读和治疗应成为未来发展方向之一;基于阅读形态与体验因技术赋能而改变的现状,图书馆应发挥引领作用,积极收集、创建或协助创建数字故事,推进阅读推广、服务与治疗的融合性发展,成为社区建设促进者、历史欣赏者和社区参与倡导者,也使阅读借助交互式数字叙事这一新载体,更好地发挥变革的力量,促进健康与幸福。 展开更多
关键词 交互式数字叙事 阅读治疗 writing New Body Worlds 加拿大
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以读促写,以写促读:北师大版初中英语新教材Writing Workshop的设计理念与实施路径
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作者 钱小芳 陈芳 朱文娟 《教学月刊(中学版)(外语教学)》 2024年第9期37-43,共7页
北师大版初中英语新教材中的Writing Workshop的设计遵循“从读听课输入到读写课输出,在单元中逐步生成写作能力”“采用读写结合模式,注重过程指导,提供多维写作支架”“从问题入手,贯穿‘学—思—用—创’一体化思路,以多元评价促学... 北师大版初中英语新教材中的Writing Workshop的设计遵循“从读听课输入到读写课输出,在单元中逐步生成写作能力”“采用读写结合模式,注重过程指导,提供多维写作支架”“从问题入手,贯穿‘学—思—用—创’一体化思路,以多元评价促学”的理念。它分两个课时进行教学:第一课时强调把握写作任务,由读到写;第二课时注重写作与评价共进,旨在切实提升学生的写作能力,发展学生的核心素养。 展开更多
关键词 北师大版新教材 writing Workshop 以读促写 以写促读
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Deep-subwavelength single grooves prepared by femtosecond laser direct writing on Si
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作者 叶瑞熙 黄敏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期108-115,共8页
It is well known that femtosecond laser pulses can easily spontaneously induce deep-subwavelength periodic surface structures on transparent dielectrics but not on non-transparent semiconductors.Nevertheless,in this s... It is well known that femtosecond laser pulses can easily spontaneously induce deep-subwavelength periodic surface structures on transparent dielectrics but not on non-transparent semiconductors.Nevertheless,in this study,we demonstrate that using high-numerical-aperture 800 nm femtosecond laser direct writing with controlled pulse energy and scanning speed in the near-damage-threshold regime,polarization-dependent deep-subwavelength single grooves with linewidths of~180 nm can be controllably prepared on Si.Generally,the single-groove linewidth increases slightly with increase in the pulse energy and decrease in the scanning speed,whereas the single-groove depth significantly increases from~300 nm to~600 nm with decrease in the scanning speed,or even to over 1μm with multi-processing,indicating the characteristics of transverse clamping and longitudinal growth of such deep-subwavelength single grooves.Energy dispersive spectroscopy composition analysis of the near-groove region confirms that single-groove formation tends to be an ultrafast,non-thermal ablation process,and the oxidized deposits near the grooves are easy to clean up.Furthermore,the results,showing both the strong dependence of groove orientation on laser polarization and the occurrence of double-groove structures due to the interference of pre-formed orthogonal grooves,indicate that the extraordinary field enhancement of strong polarization sensitivity in the deep-subwavelength groove plays an important role in single-groove growth with high stability and collimation. 展开更多
关键词 femtosecond-laser direct writing of Si deep-subwavelength single grooves polarization dependence high numerical aperture ultrafast non-thermal ablation
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Detecting LLM-assisted writing in scientific communication:Are we there yet?
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作者 Teddy Lazebnik Ariel Rosenfeld 《Journal of Data and Information Science》 CSCD 2024年第3期4-13,共10页
Large Language Models(LLMs),exemplified by ChatGPT,have significantly reshaped text generation,particularly in the realm of writing assistance.While ethical considerations underscore the importance of transparently ac... Large Language Models(LLMs),exemplified by ChatGPT,have significantly reshaped text generation,particularly in the realm of writing assistance.While ethical considerations underscore the importance of transparently acknowledging LLM use,especially in scientific communication,genuine acknowledgment remains infrequent.A potential avenue to encourage accurate acknowledging of LLM-assisted writing involves employing automated detectors.Our evaluation of four cutting-edge LLM-generated text detectors reveals their suboptimal performance compared to a simple ad-hoc detector designed to identify abrupt writing style changes around the time of LLM proliferation.We contend that the development of specialized detectors exclusively dedicated to LLM-assisted writing detection is necessary.Such detectors could play a crucial role in fostering more authentic recognition of LLM involvement in scientific communication,addressing the current challenges in acknowledgment practices. 展开更多
关键词 LLM-assisted writing Scientific communication writing style
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Scoring and Consequential Validity Evidence of Computer-and Paper-Based Writing Tests in Times of Change
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作者 María GUAPACHA-CHAMORRO Orlando CHAVES-VARÓN 《Chinese Journal of Applied Linguistics》 2024年第3期450-480,525,共32页
Little is known about how the assessment modality,i.e.,computer-based(CB)and paper-based(PB)tests,affects language teachers’scorings,perceptions,and preferences and,therefore,the validity and fairness of classroom wr... Little is known about how the assessment modality,i.e.,computer-based(CB)and paper-based(PB)tests,affects language teachers’scorings,perceptions,and preferences and,therefore,the validity and fairness of classroom writing assessments.The present mixed-methods study used Shaw and Weir’s(2007)sociocognitive writing test validation framework to examine the scoring and consequential validity evidence of CB and PB writing tests in EFL classroom assessment in higher education.Original handwritten and word-processed texts of 38 EFL university students were transcribed to their opposite format and assessed by three language lecturers(N=456 texts,152 per teacher)to examine the scoring validity of CB and PB tests.The teachers’perceptions of text quality and preferences for assessment modality accounted for the consequential validity evidence of both tests.Findings revealed that the assessment modality impacted teachers’scorings,perceptions,and preferences.The teachers awarded higher scores to original and transcribed handwritten texts,particularly text organization and language use.The teachers’perceptions of text quality differed from their ratings,and physical,psychological,and experiential characteristics influenced their preferences for assessment modality.The results have implications for the validity and fairness of CB and PB writing tests and teachers’assessment practices. 展开更多
关键词 scoring validity consequential validity CB and PB writing tests classroom assessment
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Analyzing the Essay Writing Patterns of Iranian Intermediate-Level Korean Language Learners: A Study Based on the TOPIK Exam
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作者 Vahid Reza Nasrollahi 《Sino-US English Teaching》 2024年第8期354-371,共18页
This study examines the writing abilities of Iranian intermediate Korean learners,specifically their performance in the compositional writing section of the Test of Proficiency in Korean(TOPIK).By utilizing the many F... This study examines the writing abilities of Iranian intermediate Korean learners,specifically their performance in the compositional writing section of the Test of Proficiency in Korean(TOPIK).By utilizing the many FACETS-Rasch Model,we meticulously analyzed nine writing samples from the 52nd TOPIK.These samples were evaluated using a modified rubric ranging from 0 to 3 based on predefined criteria for written composition.The results underscored that the sections on“appropriateness of spacing and spelling,”“relevance of vocabulary,”and“content diversity”presented the most significant challenges for the learners.On the other hand,“the quantity of writing”emerged as the least challenging aspect.These findings reveal substantial disparities in various aspects of writing proficiency among learners.The study not only pinpoints issue areas in writing skills,but also underscores the necessity of customized teaching strategies within the TOPIK framework to address these weaknesses.Consequently,it offers valuable insights that could bolster the effectiveness of teaching writing to Korean language learners.The findings of this study are not only significant for the field of language education,but also contribute to a deeper understanding of the challenges faced by intermediate learners and provide a roadmap for improving language instruction. 展开更多
关键词 TOPIK writing evaluation Iranian intermediate Korean learners multinational research analysis writing challenges language education strategies
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Neutral Territory:Cultural Space in Hawthorne’s Travel Writing
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作者 LI Fan PENG Shi-yu 《Cultural and Religious Studies》 2024年第7期428-433,共6页
The emphasis on the combination of physical space and metaphorical space is a major feature of Hawthorne’s narrative.This paper analyzes cultural space in Hawthorne’s travel writing,centering on his works The Old Ma... The emphasis on the combination of physical space and metaphorical space is a major feature of Hawthorne’s narrative.This paper analyzes cultural space in Hawthorne’s travel writing,centering on his works The Old Manse and The Marble Faun from the perspective of neutral territory.The old manse and Rome carry different cultural metaphors,each reflecting a complex and subtle narrative space.Individually,Hawthorne transforms the old manse into Thoreauesque cabin,where American is affected by“sleepiness”and gains spiritual healing.At the national level,Hawthorne creates an allegorical Italy as borderland to explore the existence of American civilization. 展开更多
关键词 Nathaniel Hawthorne neutral philosophy cultural space travel writing
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The “Panchatantra” Narrative Structure and the Writing of Indian Women’s Dilemma in Suraj Ka Satvan Ghoda
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作者 CEN Rui 《Journal of Literature and Art Studies》 2024年第7期567-575,共9页
Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival... Dharamvir Bharati’s Suraj Ka Satvan Ghoda connects the text with the social reality,through the multiple narrative perspectives of the“Panchatantra”Narrative Structure and the love stories,and narrates the survival and spiritual dilemma of Indian women in the transformation of India’s modernization.The novel depicts in both content and form the plight of Indian women’s physical and spiritual dependence under the traditional concepts of arranged marriages,caste marriages,dowry system and patriarchal will,and shows the process of women’s body and self-consciousness gradually moving from vitality to extinction. 展开更多
关键词 Suraj Ka Satvan Ghoda Dharamvir Bharati The“Panchatantra”narrative structure dilemma writing
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Research on Intergenerational Writing in Contemporary German Immigrant Literature
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作者 ZHOU Lei 《Sino-US English Teaching》 2024年第7期303-308,共6页
With the deepening of globalization,immigration and pluralism have become increasingly common social phenomena.The research of the resulting immigrant literature is an important way to understand the mental journey of... With the deepening of globalization,immigration and pluralism have become increasingly common social phenomena.The research of the resulting immigrant literature is an important way to understand the mental journey of immigrant groups and their construction of cultural identity.In the German-speaking area,immigrant literature has gradually taken center stage over the years,becoming an important part of the German language literature,and immigrant writers have also frequently won various literary prizes,which can be described as particularly dazzling.Meanwhile,generations of writers have been thinking about and exploring the intergenerational relationships and differences among immigrant groups in the context of their own experiences.This paper will focus on some outstanding immigrant writers and discuss the intergenerational writing in immigrant literature by means of their works. 展开更多
关键词 immigrant literature immigrant writers intergenerational writing
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English Writing Autonomy and Literacy among Chinese College Students
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作者 Chunlei Su 《Journal of Contemporary Educational Research》 2024年第8期107-113,共7页
The purpose of this study is to examine the current situation of English writing autonomy and literacy among Chinese college students,to analyze their performance,scale,and distribution as well as influencing factors,... The purpose of this study is to examine the current situation of English writing autonomy and literacy among Chinese college students,to analyze their performance,scale,and distribution as well as influencing factors,and to explore the correlation between English writing autonomy and literacy.This study will provide an in-depth analysis of the current situation of Chinese college students’English writing autonomy and literacy,reveal the scale,distribution,and influencing factors,as well as put forward strategies to enhance them,so as to provide a reference for the reform and development of college English education. 展开更多
关键词 Chinese college students English writing autonomy LITERACY Status quo Influencing factors Enhancement strategies
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A Study on the Correlation Between LIWC Word Categories and Chinese Composition Writing Performance of Fourth,Fifth,and Sixth Grade Students
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作者 Yufeng Wu 《Journal of Contemporary Educational Research》 2024年第1期199-206,共8页
This study focuses on the analysis of the Chinese composition writing performance of fourth,fifth,and sixth grade students in 16 selected schools in Longhua District,Shenzhen during the spring semester of 2023.Using L... This study focuses on the analysis of the Chinese composition writing performance of fourth,fifth,and sixth grade students in 16 selected schools in Longhua District,Shenzhen during the spring semester of 2023.Using LIWC(Linguistic Inquiry and Word Count)as a text analysis tool,the study explores the impact of LIWC categories on writing performance which is scaled by score.The results show that the simple LIWC word categories have a significant positive influence on the composition scores of lower-grade students;while complex LIWC word categories have a significant negative influence on the composition scores of lower-grade students but a significant positive influence on the composition scores of higher-grade students.Process word categories have a positive influence on the composition scores of all three grades,but the impact of complex process word categories increases as the grade level rises. 展开更多
关键词 Chinese composition LIWC word categories writing performance Grades Text mining
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A Study on the Effects of Different Interaction Combinations and Language Levels on Continuous Writing in Online Environments
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作者 Xuefei Zhu 《Journal of Contemporary Educational Research》 2024年第4期255-263,共9页
This study was conducted with non-English sophomore students,aiming to explore the effects of different interaction combinations and language levels on continuous writing in an online environment,and compare the diffe... This study was conducted with non-English sophomore students,aiming to explore the effects of different interaction combinations and language levels on continuous writing in an online environment,and compare the differences in lexical alignments and composition quality of learners with different interaction combinations and language levels in the same continuous writing task through experiments.The results show that the mean values of the word-phrase alignment of the paired group were higher than those of the individual group in different interaction combinations,and the two groups showed significant differences;in terms of composition quality,the individual group was better than the paired group,but there was no significant difference between the two groups in terms of task continuation.Secondly,the word-phrase alignment and composition scores of the different language-level groups were higher than those of the same language-level groups,and there was a significant difference between the two groups in terms of word-phrase alignments,but not in terms of composition scores.The results of this study can be useful and informative for second language teachers in future continuous teaching in online environments. 展开更多
关键词 Online environment Continuous writing Interaction combinations Language levels
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Exploring Pedagogical Ideologies and Strategies for College English Writing Instruction from a Generative Artificial Intelligence Perspective
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作者 Boya Zhang 《Journal of Contemporary Educational Research》 2024年第1期173-178,共6页
This study,drawing on the commonalities between generative artificial intelligence and foreign language writing instruction,outlines the core ideology of digital humanities-based college English writing instruction,in... This study,drawing on the commonalities between generative artificial intelligence and foreign language writing instruction,outlines the core ideology of digital humanities-based college English writing instruction,including auxiliary use of generative artificial intelligence tools,primary focus on humanistic education,and the re-production of knowledge,aiming to foster students’critical thinking,collaborative skills,and creativity.Building on this foundation,the study delves into generative artificial intelligence tools applicable to different stages of process-genre writing and their strategic applications.The use of generative artificial intelligence tools is beneficial for students to present,discuss,and share writing content,encouraging them to enhance their writing,collaboration,critical thinking,and creative abilities through deep interaction with model essays and creative discourses. 展开更多
关键词 Generative artificial intelligence College English writing instruction Process-genre approach Ideologies and strategies
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Laser direct writing of Ga_(2)O_(3)/liquid metal-based flexible humidity sensors 被引量:6
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作者 Songya Cui Yuyao Lu +5 位作者 Depeng Kong Huayu Luo Liang Peng Geng Yang Huayong Yang Kaichen Xu 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2023年第7期30-39,共10页
Flexible and wearable humidity sensors play a vital role in daily point-of-care diagnosis and noncontact human-machine interactions.However,achieving a facile and high-speed fabrication approach to realizing flexible ... Flexible and wearable humidity sensors play a vital role in daily point-of-care diagnosis and noncontact human-machine interactions.However,achieving a facile and high-speed fabrication approach to realizing flexible humidity sensors remains a challenge.In this work,a wearable capacitive-type Ga_(2)O_(3)/liquid metal-based humidity sensor is demonstrated by a one-step laser direct writing technique.Owing to the photothermal effect of laser,the Ga_(2)O_(3)-wrapped liquid metal particles can be selectively sintered and converted from insulative to conductive traces with a resistivity of 0.19Ω·cm,while the untreated regions serve as active sensing layers in response to moisture changes.Under 95%relative humidity,the humidity sensor displays a highly stable performance along with rapid response and recover time.Utilizing these superior properties,the Ga_(2)O_(3)/liquid metal-based humidity sensor is able to monitor human respiration rate,as well as skin moisture of the palm under different physiological states for healthcare monitoring. 展开更多
关键词 laser direct writing liquid metal humidity sensors flexible electronics wearable sensors
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Femtosecond laser direct writing of functional stimulus-responsive structures and applications 被引量:1
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作者 Yuxuan Zhang Dong Wu +5 位作者 Yachao Zhang Yucheng Bian Chaowei Wang Jiawen Li Jiaru Chu Yanlei Hu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第4期375-414,共40页
Diverse natural organisms possess stimulus-responsive structures to adapt to the surrounding environment.Inspired by nature,researchers have developed various smart stimulus-responsive structures with adjustable prope... Diverse natural organisms possess stimulus-responsive structures to adapt to the surrounding environment.Inspired by nature,researchers have developed various smart stimulus-responsive structures with adjustable properties and functions to address the demands of ever-changing application environments that are becoming more intricate.Among many fabrication methods for stimulus-responsive structures,femtosecond laser direct writing(FsLDW)has received increasing attention because of its high precision,simplicity,true three-dimensional machining ability,and wide applicability to almost all materials.This paper systematically outlines state-of-the-art research on stimulus-responsive structures prepared by FsLDW.Based on the introduction of femtosecond laser-matter interaction and mainstream FsLDW-based manufacturing strategies,different stimulating factors that can trigger structural responses of prepared intelligent structures,such as magnetic field,light,temperature,pH,and humidity,are emphatically summarized.Various applications of functional structures with stimuli-responsive dynamic behaviors fabricated by FsLDW,as well as the present obstacles and forthcoming development opportunities,are discussed. 展开更多
关键词 stimulus-responsive structures femtosecond laser direct writing laser–matter interaction multifunctionality
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Periodic transparent nanowires in ITO film fabricated via femtosecond laser direct writing 被引量:2
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作者 Qilin Jiang Long Chen +8 位作者 Jukun Liu Yuchan Zhang Shian Zhang Donghai Feng Tianqing Jia Peng Zhou Qian Wang Zhenrong Sun Hongxing Xu 《Opto-Electronic Science》 2023年第1期11-22,共12页
This paper reports the fabrication of regular large-area laser-induced periodic surface structures(LIPSSs)in indium tin oxide(ITO)films via femtosecond laser direct writing focused by a cylindrical lens.The regular LI... This paper reports the fabrication of regular large-area laser-induced periodic surface structures(LIPSSs)in indium tin oxide(ITO)films via femtosecond laser direct writing focused by a cylindrical lens.The regular LIPSSs exhibited good properties as nanowires,with a resistivity almost equal to that of the initial ITO film.By changing the laser fluence,the nanowire resistances could be tuned from 15 to 73 kΩ/mm with a consistency of±10%.Furthermore,the average transmittance of the ITO films with regular LIPSSs in the range of 1200-2000 nm was improved from 21%to 60%.The regular LIPSS is promising for transparent electrodes of nano-optoelectronic devices-particularly in the near-infrared band. 展开更多
关键词 transparent nanowires periodic surface nanostructures femtosecond laser direct writing ITO film anisotropic electrical conductivity
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ChatGPT as an Educational Tool: Opportunities, Challenges, and Recommendations for Communication, Business Writing, and Composition Courses 被引量:8
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作者 Mohammad Awad AlAfnan Samira Dishari +1 位作者 Marina Jovic Koba Lomidze 《Journal of Artificial Intelligence and Technology》 2023年第2期60-68,共9页
This empirical study examines ChatGPT as an educational and learning tool.It investigates the opportunities and challenges that ChatGPT provides to the students and instructors of communication,business writing,and co... This empirical study examines ChatGPT as an educational and learning tool.It investigates the opportunities and challenges that ChatGPT provides to the students and instructors of communication,business writing,and composition courses.It also strives to provide recommendations.After conducting 30 theory-based and application-based ChatGPT tests,it is found that ChatGPT has the potential of replacing search engines as it provides accurate and reliable input to students.For opportunities,the study found that ChatGPT provides a platform for students to seek answers to theory-based questions and generate ideas for application-based questions.It also provides a platform for instructors to integrate technology in classrooms and conduct workshops to discuss and evaluate generated responses.For challenges,the study found that ChatGPT,if unethically used by students,may lead to human unintelligence and unlearning.This may also present a challenge to instructors as the use of ChatGPT negatively affects their ability to differentiate between meticulous and automation-dependent students,on the one hand,and measure the achievement of learning outcomes,on the other hand.Based on the outcome of the analysis,this study recommends communication,business writing,and composition instructors to(1)refrain from making theory-based questions as take-home assessments,(2)provide communication and business writing students with detailed case-based and scenario-based assessment tasks that call for personalized answers utilizing critical,creative,and imaginative thinking incorporating lectures and textbook material,(3)enforce submitting all take-home assessments on plagiarism detection software,especially for composition courses,and(4)integrate ChatGPT generated responses in classes as examples to be discussed in workshops.Remarkably,this study found that ChatGPT skillfully paraphrases regenerated responses in a way that is not detected by similarity detection software.To maintain their effectiveness,similarity detection software providers need to upgrade their software to avoid such incidents from slipping unnoticed. 展开更多
关键词 artificial intelligence business writing courses ChatGPT composition courses communication courses Turnitin
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Automated writing evaluation(1995-2022):Research trends and implications 被引量:1
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作者 ZHANG TINGYU LEI LEI 《语言测试与评价》 2023年第1期61-88,123,共29页
Automated writing evaluation is the use of computer programs to evaluate essays written in an educational setting.This study aims to evaluate the state of the art and the trends of automated writing evaluation researc... Automated writing evaluation is the use of computer programs to evaluate essays written in an educational setting.This study aims to evaluate the state of the art and the trends of automated writing evaluation research.A total of 206 automated writing evaluation-related publications published in 88 journals between 1995 and 2022 were used as the data in our study.Bibliometric methods were employed to identify the publication trends,venues for publication,productive authors,highly cited articles,seminal works,and the most frequently explored topics across the past decades.The findings show that automated writing evaluation has become a fast-growing interdisciplinary area of interest.In addition,this line of research has witnessed a growing interest in topics pertaining to the latest technology,the perception of children,the teachers’feedback,and complex tasks.Implications of our study for future research are also discussed. 展开更多
关键词 automated writing evaluation research trends bibliometric analysis
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Direct ink writing to fabricate porous acetabular cups from titanium alloy
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作者 Naima Valentin Weijian Hua +3 位作者 Ashish K.Kasar Lily Raymond Pradeep L.Menezes Yifei Jin 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2023年第2期121-135,共15页
Acetabular cups,which are among themost important implants in total hip arthroplasty,are usually made from titanium alloys with high porosity and adequate mechanical properties.The current three-dimensional(3D)printin... Acetabular cups,which are among themost important implants in total hip arthroplasty,are usually made from titanium alloys with high porosity and adequate mechanical properties.The current three-dimensional(3D)printing approaches to fabricate customized acetabular cups have some inherent disadvantages such as high cost and energy consumption,residual thermal stress,and relatively low efficiency.Thus,in this work,a direct ink writing method was developed to print a cup structure at room temperature,followed by multi-step heat treatment to form microscale porous structure within the acetabular cup.Our method is facilitated by the development of a self-supporting titanium-6 aluminum-4 vanadium(Ti64)ink that is composed of Ti64 particles,bentonite yield-stress additive,ultraviolet curable polymer,and photo-initiator.The effects of Ti64 and bentonite concentrations on the rheological properties and printability of inks were systematically investigated.Moreover,the printing conditions,geometrical limitations,and maximum curing depth were explored.Finally,some complex 3D structures,including lattices with different gap distances,honeycomb with a well-defined shape,and an acetabular cup with uniformly distributed micropores,were successfully printed/fabricated to validate the effectiveness of the proposed method. 展开更多
关键词 Acetabular cup Direct ink writing Titanium alloy BENTONITE Heat treatment
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A systematic printability study of direct ink writing towards high-resolution rapid manufacturing
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作者 Qingyang Zheng Bin Xie +1 位作者 Zhoulong Xu Hao Wu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2023年第3期500-517,共18页
Direct ink writing(DIW)holds enormous potential in fabricating multiscale and multi-functional architectures by virtue of its wide range of printable materials,simple operation,and ease of rapid prototyping.Although i... Direct ink writing(DIW)holds enormous potential in fabricating multiscale and multi-functional architectures by virtue of its wide range of printable materials,simple operation,and ease of rapid prototyping.Although it is well known that ink rheology and processing parameters have a direct impact on the resolution and shape of the printed objects,the underlying mechanisms of these key factors on the printability and quality of DIW technique remain poorly understood.To tackle this issue,we systematically analyzed the printability and quality through extrusion mechanism modeling and experimental validating.Hybrid non-Newtonian fluid inks were first prepared,and their rheological properties were measured.Then,finite element analysis of the whole DIW process was conducted to reveal the flow dynamics of these inks.The obtained optimal process parameters(ink rheology,applied pressure,printing speed,etc)were also validated by experiments where high-resolution(<100μm)patterns were fabricated rapidly(>70 mm s^(-1)).Finally,as a process research demonstration,we printed a series of microstructures and circuit systems with hybrid inks and silver inks,showing the suitability of the printable process parameters.This study provides a strong quantitative illustration of the use of DIW for the high-speed preparation of high-resolution,high-precision samples. 展开更多
关键词 direct ink writing extrusion mechanism modelling computational fluid dynamic(CFD) printability process parameters high-resolution printing
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