High-Power Raman Soliton Generation at 1.7 μm in All-Fiber Polarization-Maintaining Erbium-Doped Amplifier

An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdoped oscillator and two-stage amplifiers with polarization maintaining commercial silica fibers and devices, which can provide robust and stable soliton generation. High-power soliton laser with the average power of 0.28 W,the repetition rate of 42.7 MHz, and pulse duration of 515 fs is generated directly from the main amplifier.Our experiment provides a feasible method for high-power all-fiber polarization maintaining femtosecond laser generation working at 1.7 μm.

A continuous and long-term in-situ stress measuring method based on fiber optic. Part I: Theory of inverse differential strain analysis

A method for in-situ stress measurement via fiber optics was proposed. The method utilizes the relationship between rock mass elastic parameters and in-situ stress. The approach offers the advantage of long-term stress measurements with high spatial resolution and frequency, significantly enhancing the ability to measure in-situ stress. The sensing casing, spirally wrapped with fiber optic, is cemented into the formation to establish a formation sensing nerve. Injecting fluid into the casing generates strain disturbance, establishing the relationship between rock mass properties and treatment pressure.Moreover, an optimization algorithm is established to invert the elastic parameters of formation via fiber optic strains. In the first part of this paper series, we established the theoretical basis for the inverse differential strain analysis method for in-situ stress measurement, which was subsequently verified using an analytical model. This paper is the fundamental basis for the inverse differential strain analysis method.

Microstructural evolution and strengthening mechanism of aligned steel fiber cement-based tail backfills exposed to electromagnetic induction

Cemented tailings backfill(CTB)not only boosts mining safety and cuts surface environmental pollution but also recovers ores previously retained as pillars,thereby improving resource utilization.The use of alternative reinforcing products,such as steel fiber(SF),has continuously strengthened CTB into SFCTB.This approach prevents strength decreases over time and reinforces its long-term durability,especially when mining ore in adjacent underground stopes.In this study,various microstructure and strength tests were performed on SFCTB,considering steel fiber ratio and electromagnetic induction strength effects.Lab findings show that combining steel fibers and their distribution dominantly influences the improvement of the fill’s strength.Fill’s strength rises by fiber insertion and has an evident correlation with fiber insertion and magnetic induction strength.When magnetic induction strength is 3×10^(-4) T,peak uniaxial compressive stress reaches 5.73 MPa for a fiber ratio of 2.0vol%.The cracks’expansion mainly started from the specimen’s upper part,which steadily expanded downward by increasing the load until damage occurred.The doping of steel fiber and its directional distribution delayed crack development.When the doping of steel fiber was 2.0vol%,SFCTBs showed excellent ductility characteristics.The energy required for fills to reach destruction increases when steel-fiber insertion and magnetic induction strength increase.This study provides notional references for steel fibers as underground filling additives to enhance the fill’s durability in the course of mining operations.

Relationship of Retinal Nerve Fiber Layer Thickness and Retinal Vessel Calibers with Cognitive Impairment in the Asymptomatic Polyvascular Abnormalities Population

Objective Cognitive impairment(CI)in older individuals has a high morbidity rate worldwide,with poor diagnostic methods and susceptible population identification.This study aimed to investigate the relationship between different retinal metrics and CI in a particular population,emphasizing polyvascular status.Methods We collected information from the Asymptomatic Polyvascular Abnormalities Community Study on retinal vessel calibers,retinal nerve fiber layer(RNFL)thickness,and cognitive function of 3,785participants,aged 40 years or older.Logistic regression was used to analyze the relationship between retinal metrics and cognitive function.Subgroups stratified by different vascular statuses were also analyzed.Results RNFL thickness was significantly thinner in the CI group(odds ratio:0.973,95%confidence interval:0.953–0.994).In the subgroup analysis,the difference still existed in the non-intracranial arterial stenosis,non-extracranial carotid arterial stenosis,and peripheral arterial disease subgroups(P<0.05).Conclusion A thin RNFL is associated with CI,especially in people with non-large vessel stenosis.The underlying small vessel change in RNFL and CI should be investigated in the future.

Genetic dissection and origin of pleiotropic loci underlying multilevel fiber quality traits in upland cotton(Gossypium hirsutum L.)

Cotton fiber quality is a persistent concern that determines planting benefits and the quality of finished textile products.However,the limitations of measurement instruments have hindered the accurate evaluation of some important fiber characteristics such as fiber maturity,fineness,and neps,which in turn has impeded the genetic improvement and industrial utilization of cotton fiber.Here,12 single fiber quality traits were measured using Advanced Fiber Information System(AFIS)equipment among 383 accessions of upland cotton(Gossypium hirsutum L.).In addition,eight conventional fiber quality traits were assessed by the High Volume Instrument(HVI)System.Genome-wide association study(GWAS),linkage disequilibrium(LD)block genotyping and functional identification were conducted sequentially to uncover the associated elite loci and candidate genes of fiber quality traits.As a result,the previously reported pleiotropic locus FL_D11 regulating fiber length-related traits was identified in this study.More importantly,three novel pleiotropic loci(FM_A03,FF_A05,and FN_A07)regulating fiber maturity,fineness and neps,respectively,were detected based on AFIS traits.Numerous highly promising candidate genes were screened out by integrating RNA-seq and qRT-PCR analyses,including the reported GhKRP6 for fiber length,the newly identified GhMAP8 for maturity and GhDFR for fineness.The origin and evolutionary analysis of pleiotropic loci indicated that the selection pressure on FL_D11,FM_A03 and FF_A05 increased as the breeding period approached the present and the origins of FM_A03 and FF_A05 were traced back to cotton landraces.These findings reveal the genetic basis underlying fiber quality and provide insight into the genetic improvement and textile utilization of fiber in G.hirsutum.

Retinal nerve fiber layer defects and chronic kidney disease:the Kailuan Eye Study

AIM:To investigate whether retinal nerve fiber layer defects(RNFLDs)is a potential risk factor for chronic kidney disease(CKD)in Chinese adults.METHODS:The Kailuan Eye Study was a populationbased study that included 14440 participants.All participants underwent detailed assessments,RNFLDs were diagnosed using color fundus photographs.RESULTS:Overall,12507 participants[8533 males(68.23%)]had complete systemic examination data and at least one evaluable fundus photograph.RNFLDs were found in 621 participants[5.0%;95%confidence interval(CI):4.6%-5.34%],and 70 cases of multiple RNFLDs were found(11.27%).After adjusting multiple factors,RNFLDs was significantly associated with CKD severity,the ORs of CKD stage 3,stage 4 and stage 5 were 1.698,4.167,and 9.512,respectively.Multiple RNFLDs were also associated with CKD severity after adjusting multiple factors,the ORs of CKD stage 3 and stage 5 were 4.465 and 11.833 respectively.Furthermore,2294 participants had CKD(18.34%,95%CI:17.68%-18.99%).After adjusting for other factors,CKD presence was significantly correlated with the presence of RNFLDs.CONCLUSION:The strongest risk factors for RNFLDs are CKD and hypertension.Conversely,RNFLDs can be an ocular feature in patients with CKD.Fundoscopy can help detect systemic diseases,and assessment for RNFLDs should be considered in CKD patients.

Study of damage behavior and repair effectiveness of patch repaired carbon fiber laminate under quasi-static indentation loading

Damage caused due to low-velocity impacts in composites leads to substantial deterioration in their residual strength and eventually provokes structural failure.This work presents an experimental investigation on the effects of different patch and parent laminate stacking sequences on the enhancement of impact strength of Carbon Fiber Reinforced Polymers(CFRP)composites by utilising the adhesively bonded external patch repair technique.Damage evolution study is also performed with the aid of Acoustic Emission(AE).Two different quasi-isotropic configurations were selected for the parent laminate,viz.,[45°/45°/0°/0°]s and[45°/0°/45°/0°]s.Quasi Static Indentation(QSI)test was performed on both the pristine laminates,and damage areas were detected by using the C-scan inspection technique.Damaged laminates were repaired by using a single-sided patch of two different configurations,viz.,[45°/45°/45°/45°]and[45°/0°/0°/45°],and employing a circular plug to fill the damaged hole.Four different combinations of repaired laminates with two configurations of each parent and patch laminate were produced,which were further subjected to the QSI test.The results reveal the effectiveness of the repair method,as all the repaired laminates show higher impact resistance compared to the respective pristine laminates.Patches of[45°/0°/0°/45°]configuration when repaired by taking[45°/45°/0°/0°]s and[45°/0°/45°/0°]s as parents exhibited 68%and 73%higher peak loads,respectively,than the respective pristine laminates.Furthermore,parent and patch of configuration[45°/0°/45°/0°]s and[45°/0°/0°/45°],respectively,attain the highest peak load,whereas[45°/45°/0°/0°]s and[45°/45°/45°/45°]combinations possess the most gradual decrease in the load.

Comparison of the Clinical Effect of Prefabricated Fiber Post and Plastic Fiber Post in Oral Repair

Objective:To observe and analyze the clinical effect of prefabricated fiber posts and plastic fiber posts in oral repair.Methods:A total of 128 patients admitted to our hospital from January 2023 to June 2024 underwent oral prosthesis treatment,of which the control group(n=64)was treated with prefabricated fiber posts and the observation group(n=64)with plastic fiber posts.The efficacy,retention rate,and complication rate of the two groups were compared.Results:The total effective rate of the observation group was 96.88%,which was significantly higher than that of the control group(84.38%)(P<0.05).The restoration retention rate in the observation group was 95.31%,which was significantly higher than that in the control group(85.94%)(P<0.05).The incidence of postoperative complications in the observation group was 4.69%,which was significantly lower than that in the control group(15.63%)(P<0.05).Conclusion:For patients with oral prostheses,the use of plastic fiber posts for treatment shows better clinical effects,effectively improving the retention rate of the prosthesis and reducing the incidence of complications.Thus,it is worthy of popularization and application.

AI赋能视角下的信息行为研究--2023年信息行为研究年会综述

2023年12月23—24日,2023年信息行为研究年会在北京大学召开,来自全国70多所高校的200余位知名专家学者和学生参加了会议。本次年会以“AI赋能视角下的信息行为研究”为主题,设置了主旨报告、专题讨论、海报展示、分论坛报告、眼动追踪工作坊等环节,围绕信息行为研究领域在新一代人工智能(AI)技术浪潮下的理论创新、方法应用、情境拓展、人本关怀、社会发展等方面进行深入研讨。文章综述了与会者的学术成果与主要观点,为信息行为研究的发展与创新提供理论启迪与研究指引。

生成式AI视域下智慧图书馆建设的关键路径

[目的/意义]智慧图书馆已经成为当今图书馆学界和业界最热门的主题之一。智慧图书馆建设的理论研究与实践工作已经取得了初步成效,生成式AI也在蓬勃发展的同时参与到各行各业的建设中。因此有必要立足当下发展,放眼远景目标,确定生成式AI参与智慧图书馆建设的策略。[方法/过程]本文从智慧图书馆空间升级、服务打造、业务重组、人才培养、体系建设5个方面阐明了生成式AI视域下智慧图书馆建设的关键路径。[结果/结论]关键路径研究将为生成式AI引入智慧图书馆下一阶段的建设工作提供借鉴与依据。

用户知识问答转移行为研究:从问答社区到生成式AI

[研究目的]作为一类新兴应用,生成式AI在知识问答领域吸引了众多用户,这可能导致传统的知识问答社区用户流失,因此研究用户转移行为对提高知识问答社区用户粘性来说至关重要。[研究方法]基于PPM(推-拉-锚)模型,整合认知和情感体验因素,研究了用户的知识问答转移行为。对收集的483份有效数据采用混合方法包括结构方程模型(SEM)和模糊集定性比较分析(fsQCA)进行分析。[研究结论]研究结果发现,转移意愿受推力因素(信息过载、社区倦怠)、拉力因素(感知拟人度、感知准确度、感知可信度、沉浸体验)和锚定因素(社会影响)的综合影响。fsQCA识别出了三条导致转移意愿的主要路径。研究结果启示问答社区需降低信息过载,缓解用户的社区倦怠,从而实现用户保持和平台可持续发展。

Sora的职业影响:知识工作者应对AI核心技能替代的策略

AIGC技术的快速发展使人类独有的核心技能逐渐被AI突破和替代,这一趋势给知识工作者带来了前所未有的挑战和焦虑。文章分析OpenAI最新发布的Sora视频生成模型引发的岗位替代威胁,探讨知识工作者应对挑战的策略:采用“人在环中”(HITL)的工作策略、促进多AI智能体之间的协作、利用AI工具学习和掌握新的AI知识和技能,助力知识工作者既能维持职场竞争力,又能探索和创造AI时代新的工作机会。

生成式AI影响下的艺术媒介本体论转向

以Midjourney为代表的生成式AI模型中的“文字转图像”(Text-to-image)技术正在被广泛应用,其崭新的交互方式向大众宣告了生成式AI带领当代艺术步入“艺术大众化”时代。生成式AI技术影响下的艺术传播媒介发生了巨大变迁。艺术媒介已不仅具有“材料”“媒材”“质料”等传统属性,艺术传播的媒介环境从“再现”走向“再生产”;艺术媒介从“聚块”(Agglomerations)的传播模式发展为多元形态,在分散且广泛的“灰色媒介”中,艺术媒介的“物质性”被关注;人机艺术传播中的“媒介在场”和“社会在场”共同建构社会景观,塑造社会现实。

新农科背景下基于AI昆虫识别软件的实验教学改革

从昆虫智能识别入手开展新农科背景下昆虫学的实验教学改革和实践。软件由昆虫图片上传、模型训练、目标检测以及导出结果4个模块组成。完成目标检测的图片根据需要保存。AI昆虫识别软件的开发过程在Visual Studio Code环境下进行,采用Python语言进行编程,实现对拍摄图片的高效率、高精度检测。最后拟通过学生本科实验教学环节,开放成为农科学生进行昆虫识别鉴定的实践工具,极大激发农科学生的上课激情,同时也有助于在新农科背景下培养农科类学生的现代农业创新思维。

以ChatGPT为代表的AI技术与高等教育的深度融合

随着人工智能技术飞速发展,以ChatGPT为代表的人工智能技术已经逐渐成为人们关注的焦点。旨在探讨ChatGPT技术与高等教育的深度融合研究,分析其对高等教育的影响和挑战,并提出相应的解决方案。首先,介绍了ChatGPT技术的基本原理和特点,包括其语言生成模型的构建、预训练和优化等;然后,通过分析ChatGPT技术在高等教育中的应用场景,如智能教育、在线教学、个性化推荐等,探讨了其对高等教育的影响和挑战;最后,提出了一些解决方案,比如加强ChatGPT技术与高等教育的深度融合、建立完善的教育监管机制等,以应对ChatGPT技术在高等教育中面临的挑战。

基于AI算法的自然语言信息提取-翻译-校对系统设计

自20世纪90年代起,随着人工智能(AI)的飞速发展及其与深度学习等机器学习方法的广泛融合,自然语言处理(NLP)作为人工智能的核心,也取得了令人瞩目的进步。而随着国际学术交流、世界文化交融愈加频繁,人们搜寻、阅读他国网络信息的现实需求也随之增多。当信息搜寻者在搜寻非母语信息时,不仅会出现语言障碍问题,还会因错综复杂、层次不齐的各色信息而产生诸多不便。为了便于信息搜寻者快速高效地获取有用信息,文中基于人工智能算法(PageRank/TextRank)设计一种信息提取-翻译-校对(ETP)系统。系统通过AI自动搜索阅读页面上的重要信息和文本摘取,生成摘要,并基于机器翻译API模块完成翻译;其次,采用智能校对系统完成校对审核后,将信息呈现给搜寻者,以供其对全部信息高效且准确地进行预筛选,从而节省阅读时间和精力。最后对系统算法所实现的功能进行实验测试,结果达到预期。

基于AI的肺磨玻璃结节中医临床特点研究

目的通过客观、规范的方法分析肺磨玻璃中医临床特点,利用人工智能(AI)分析肺磨玻璃结节恶性风险,初步探究不同风险肺磨玻璃结节中医临床特点,为中医药干预肺结节提供参考。方法采集75例肺磨玻璃结节患者中医四诊信息,运用证素辨证方法提取证素;利用AI判读患者胸部CT,分析不同风险肺磨玻璃结节中医临床特点。结果肺磨玻璃结节患者中医证素以阴虚(77.33%)、气虚(56.00%)、阳虚(54.67%)、血虚(52.00%)等证素多见,亦可见痰(40.00%)、寒(37.33%)、气滞(32.00%)等实性证素;AI判读为高风险组较中低风险组气虚证素权值差异有统计学意义(P<0.05)。结论肺磨玻璃结节患者中医辨证以虚证为主,中医病机为气虚或气滞导致肺之气机不畅,引起局部痰、湿聚集于肺络而形成,而热证、瘀血证较少。

AI涌现:国际传播生态新物种、新范式和新秩序

以Chat GPT为代表的生成式AI进入国际传播生态,兼具生产者和消费者双重身份,成为传播新物种。人机共存、人机共有、人机共创将是国际传播的新面向。生成式AI在与既有传播主体的碰撞与融合中,催生了国际传播新范式,但同时也伴随着虚假信息泛滥、技术发展失衡和违背伦理法规等风险。因此,国际传播的新秩序亟待重构,从全方位提升国际传播主体能力、多层次多角度展开叙事内容和全过程治理传播等方向构建新秩序或是可行之路。

5G专网部署AI大模型能力的研究

为满足行业终端安全接入组织专网的移动性需求,能随时以自然语言交流方式实现行业应用与知识库的人机交互,文章对5G专网和交互式AI模型应用部署进行研究,阐述了在5G专网中部署行业AI大模型能力的解决方案,通过网络切片、安全策略和边缘云计算的部署方案解决网络安全和信息交互时延等问题,从而拓展5G专网在AI领域的应用场景,保障行业信息和敏感数据,提升工作效率。

结合地理信息与AIS数据的海上航道自适应提取方法

海上航道对于海上态势感知具有重要意义。然而,现有的航道提取方法存在航道航路点易丢失、提取准确性不高等问题,本文依据船舶航路点数量与其途经岛屿、港口等地理区域数量相等的准则,提出了一种结合地理信息与自动识别系统(Automatic Identification System, AIS)数据的海上航道自适应提取方法。首先,构建港口之间往返船只AIS航迹数据集,将每条AIS航迹等间距分段并计算每段航迹的平均航速,设置航速差初始阈值,计算相邻航段平均航速差超过阈值的数量作为初始船只转弯次数。其次,统计AIS航迹途经岛屿、港口等地理区域的数量,若其与利用AIS航迹提取的船舶转弯次数不相等,则根据两者的差异自适应调整航速差阈值,重新提取船舶航路点,直至其与途经地理区域的数量相等,将平均航速差超出最终阈值的航迹段的连接点作为船舶航路点。然后,利用基于密度的聚类算法将所有船舶的航路点聚类为航路点集合,计算航路点集合的质心作为航道的航路点。最后,以航道航路点为顶点、航路点之间的连线为边构建有向图,并删除落在陆地上的连线后得到最终的航道提取结果。利用潍坊港—连云港港之间行驶的20条船舶的AIS数据开展了海上航道提取实验,结果表明,与基于交通路径异常检测的航道提取方法相比,本文方法得到的船舶航路点的平均虚检率降低了9.1%,平均漏检率降低了16.7%,显著提升了航道航路点位置提取的准确性。