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叶尖小翼对Stage 37压气机级稳定裕度的影响
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作者 钟兢军 王缘 +1 位作者 赵傲 吴宛洋 《航空动力学报》 北大核心 2025年第3期369-379,共11页
为了进一步研究叶尖小翼对跨声速压气机级稳定工作裕度的影响,采用数值方法对NASA Stage 37压气机级加装不同叶尖小翼的效果进行了研究。通过对比原型压气机级与加装叶尖小翼压气机级的流场特性,揭示了压力面叶尖小翼的扩稳机理。研究... 为了进一步研究叶尖小翼对跨声速压气机级稳定工作裕度的影响,采用数值方法对NASA Stage 37压气机级加装不同叶尖小翼的效果进行了研究。通过对比原型压气机级与加装叶尖小翼压气机级的流场特性,揭示了压力面叶尖小翼的扩稳机理。研究结果表明:随着压力面小翼宽度增加,压气机级的稳定工作裕度分别提高了7.35%、12.27%、19.49%、12.34%。压力面小翼的扩稳机理在于有效减弱了泄漏涡与激波的干涉程度,改善了转子区域的通流情况,同时减弱了下游静子的吸力面分离,使得静子区域低能流体减少,降低了流动损失。 展开更多
关键词 叶尖小翼 stage 37压气机级 叶顶泄漏 稳定工作裕度 扩稳机理
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基于CrossStage-YOLO的跨阶段作物害虫检测 被引量:1
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作者 贾岚 徐雪环 +4 位作者 罗德弢 胡梦蝶 邓钦文 高文新 蒲海波 《南京农业大学学报》 北大核心 2025年第3期744-754,共11页
[目的]为了克服作物害虫在不同生长阶段的形态差异对模型检测造成的负面影响,本文提出了一种基于改进YOLOv7-tiny的跨阶段作物害虫检测模型CrossStage-YOLO。[方法]在YOLOv7-tiny的主干网络中结合重新构建的ELAN-D模块,实现降低计算内... [目的]为了克服作物害虫在不同生长阶段的形态差异对模型检测造成的负面影响,本文提出了一种基于改进YOLOv7-tiny的跨阶段作物害虫检测模型CrossStage-YOLO。[方法]在YOLOv7-tiny的主干网络中结合重新构建的ELAN-D模块,实现降低计算内存消耗的同时提高特征提取速度;引入感受野增强模块(RFE),提升模型对害虫特征和位置的感知能力;嵌入BiFormer注意力机制,提高模型对害虫头部、触须等细微特征的敏感度。[结果]CrossStage-YOLO的平均精度均值为88.6%,相对于原始模型提高3.0%;对成虫和幼虫检测的平均精度均值分别达到90.8%和81.1%,较原始模型分别提高3.3%和2.0%;并且模型以6.79 M的低参数量实现0.043 s的单张图片检测时间,综合性能优于主流目标检测模型。[结论]CrossStage-YOLO模型能够有效提升作物害虫不同生长阶段的检测准确率,为作物害虫检测的自动化诊断提供了可靠的技术支持。 展开更多
关键词 YOLOv7-tiny 跨阶段害虫检测 绿色农业 深度学习 智慧农业
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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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Mismatch between Reality and the NCFSE 2023:Focusing on the Pedagogical Challenges Faced by the Foundational and Preparatory Stage Teachers
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作者 Prasanna S K Chellamani 《Journal of Contemporary Educational Research》 2025年第5期201-207,共7页
Teacher education at the foundational and preparatory stages plays a crucial role in shaping early childhood learning experiences.The National Curriculum Framework for School Education(NCFSE)2023 provides a structured... Teacher education at the foundational and preparatory stages plays a crucial role in shaping early childhood learning experiences.The National Curriculum Framework for School Education(NCFSE)2023 provides a structured pedagogical approach to address challenges in these stages.However,despite these policy frameworks,teachers in Kendriya Vidyalayas(KVs)continue to face numerous pedagogical challenges.This paper aims to explore and analyze the pedagogical challenges encountered by KV teachers in foundational and preparatory stage classrooms and compare them with the challenges addressed in NCFSE 2023.Using qualitative research methods,data were collected through structured online interviews with 10 KV teachers from different campuses.This paper investigated various challenges,including classroom management,language barriers,a lack of inclusive education strategies,insufficient infrastructure,limited parental involvement,and difficulties in integrating technology into teaching practices.The findings highlight the gap between policy recommendations and ground-level implementation.Based on these insights,the study suggests recommendations such as specialized teacher training,recruitment of special educators,improved infrastructure,enhanced parental engagement,and policy-driven interventions to bridge the gap between policy frameworks and real-world classroom experiences.The study concludes that addressing these challenges through targeted reforms can create a more inclusive and effective learning environment,fostering holistic student development at the foundational and preparatory stages. 展开更多
关键词 Foundational stage teachers NCFSE 2023 NEP 2020 Pedagogical challenges Preparatory stage teachers
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The prognostic value of the 8th American Joint Committee on cancer anatomic and prognostic stage groups for penile cancer:A multicenter collaboration study
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作者 Xueying Li Yepeng Guo +8 位作者 Antonio Augusto Ornellas Jiun-Hung Geng Yonghong Li Wayne Lam Yabing Cao Zhuowei Liu Hui Han Fangjian Zhou Zaishang Li 《Asian Journal of Urology》 2025年第1期100-105,共6页
Objective The aim of this study was to investigate the value of the 8th American Joint Committee on Cancer(AJCC)anatomic and prognostic stage groups for penile cancer patients and explore whether there is room for imp... Objective The aim of this study was to investigate the value of the 8th American Joint Committee on Cancer(AJCC)anatomic and prognostic stage groups for penile cancer patients and explore whether there is room for improvement.Methods The clinical and histopathologic data from 16 centers between January 2000 and December 2021 were assessed according to the 8th AJCC anatomic and prognostic stage groups.Kaplan–Meier plots were used to estimate the disease-specific survival(DSS)of the patients.The accuracy of the staging systems was investigated using the Harrell's concordance index(C-index).Results According to the 8th AJCC anatomic and prognostic stage groups,the 5-year DSS rates for patients with stages 0is/a,I,IIA,IIB,IIIA,IIIB,and IV disease were 100%,99%,86%,81%,66%,34%,and 23%,respectively(p_(0is/a–I)=0.8,p_(I–IIA)<0.001,p_(IIA–IIB)=0.5,p_(IIB–IIIA)<0.001,p_(IIIA–IIIB)<0.001,p_(IIIB–IV)=0.004,and p_(Total)<0.001).According to the modified model 1 system,the 5-year DSS rates without survivorship overlap for patients with stages 0is/a,I,II,IIIA,IIIB,and IV disease were 100%,99%,88%,66%,34%,and 23%,respectively(p_(0is/a–I)=0.8,p_(I–II)<0.001,p_(II–IIIA)=0.002,p_(IIIA–IIIB)<0.001,p_(IIIB–IV)=0.004,and p_(Total)<0.001).Similarly,according to the modified model 2 system,the 5-year DSS rates without survivorship overlap for patients with stages 0is/a,I,II,IIIA,IIIB,and IV disease were 100%,99%,86%,66%,34%,and 23%,respectively(p_(0is/a–I)=0.8,p_(I–II)<0.001,p_(II–IIIA)=0.008,p_(IIIA–IIIB)<0.001,p_(IIIB–IV)=0.004,and p_(Total)<0.001).The C-index scores of the simple modified staging systems were not inferior to those of the AJCC anatomic and prognostic stage groups.These results were confirmed by the bootstrap internal validation.Conclusion There is still room for improvement about the 8th AJCC anatomic and prognostic stage groups.The improved models,which are more concise and convenient,have similar prediction accuracy. 展开更多
关键词 Penile cancer Prognosis Tumor-nodemetastasis Survival stage
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Design,Analysis,and Testing of a Novel 5-DOF Flexure-Based Alignment Stage
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作者 Shang Yang Yuxia Li +3 位作者 Weihai Chen Shasha Chen Lei Wang Xiantao Sun 《Chinese Journal of Mechanical Engineering》 2025年第4期1-15,共15页
A high pattern resolution is critical for fabricating roll-to-roll printed electronics(R2RPE)products.For enhanced overlay alignment accuracy,position errors between the printer and the substrate web must be eliminate... A high pattern resolution is critical for fabricating roll-to-roll printed electronics(R2RPE)products.For enhanced overlay alignment accuracy,position errors between the printer and the substrate web must be eliminated,particularly in inkjet printing applications.This paper proposes a novel five-degree-of-freedom(5-DOF)flexure-based alignment stage to adjust the posture of an inkjet printer head.The stage effectively compensates for positioning errors between the actuation mechanism and manipulated objects through a series-parallel combination of compliant substructures.Voice coil motors(VCMs)and linear motors serve as actuators to achieve the required motion.Theoretical models were established using a pseudo-rigid-body model(PRBM)methodology and were validated through finite element analysis(FEA).Finally,an alignment stage prototype was fabricated for an experiment.The prototype test results showed that the developed positioning platform attains 5-DOF motion capabilities with 335.1μm×418.9μm×408.1μm×3.4 mrad×3.29 mrad,with cross-axis coupling errors below 0.11%along y-and z-axes.This paper pro-poses a novel 5-DOF flexure-based alignment stage that can be used for error compensation in R2RPE and effectively improves the interlayer alignment accuracy of multi-layer printing. 展开更多
关键词 Flexible mechanism Micro-positioning Multi-DOF Alignment stage
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Discussion of“Prediction of the undrained shear strength of remolded soil with non-linear regression,fuzzy logic,and artificial neural network”[J.Mt.Sci.21(9):3108–3122]
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作者 Amin SOLTANI Brendan C.O’KELLY 《Journal of Mountain Science》 2025年第7期2723-2730,共8页
This opinion article discusses the original research work of Yünkül et al.(the Authors)published in the Journal of Mountain Science 21(9):3108–3122.Employing non-linear regression,fuzzy logic and artificial... This opinion article discusses the original research work of Yünkül et al.(the Authors)published in the Journal of Mountain Science 21(9):3108–3122.Employing non-linear regression,fuzzy logic and artificial neural network modeling techniques,the Authors interrogated a large database assembled from the existing research literature to assess the performance of twelve equation rules in predicting the undrained shear strength(s_(u))mobilized for remolded fine-grained soils at different values of liquidity index(I_(L))and water content ratio.Based on their analyses,the Authors proposed a simple and reportedly reliable correlation(i.e.,Eq.9 in their paper)for predicting s_(u) over the I_(L) range of 0.15 to 3.00.This article describes various shortcomings in the Authors’assembled database(including potentially anomalous data and covering an excessively wide I_(L) range in relation to routine geotechnical and transportation engineering applications)and their proposed s_(u)=f(I_(L))correlation.Contrary to the Authors’assertions,their proposed correlation is not reliable for fine-grained soils with consistencies in the general firm to stiff range(i.e.,for 0.15<I_(L)<0.40),increasingly overestimating s_(u) for reducing I_(L),and eventually predicting s_(u)→+∞for I_(L)→0.15+(while producing mathematically undefined s_(u) for I_(L)<0.15),thus rendering their correlation unconservative and potentially leading to unsafe geotechnical designs.Exponential or regular-power type s_(u)=f(I_(L))models are more s_(u)itable when developing correlations that are applicable over the full plastic range(of 0<I_(L)<1),thereby providing reasonably conservative s_(u) predictions for use in the preliminary design for routine geotechnical engineering applications. 展开更多
关键词 Undrained shear strength Liquidity index Soil consistency non-linear regression
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The Growing Stages of Peanuts
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作者 赵鑫阳 《疯狂英语(双语世界)》 2025年第3期60-62,共3页
Peanuts are widely produced and commonly eaten in China.They grow well in warm climates with moderate rainfall and sandy soil,and they have a relatively long growing season.In China,the main peanut-producing areas are... Peanuts are widely produced and commonly eaten in China.They grow well in warm climates with moderate rainfall and sandy soil,and they have a relatively long growing season.In China,the main peanut-producing areas are Henan,Shandong,and Hebei provinces.From planting to harvest,peanuts go through five main stages. 展开更多
关键词 hebei provinces china SHANDONG HENAN growing stages peanuts
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Non-Linear Increase of the Real Contact Area of PMMA Blocks and the Related Contact Model
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作者 Zhijun Luo Kai Wu Shaoze Yan 《Chinese Journal of Mechanical Engineering》 2025年第1期261-272,共12页
Many experiments have supported the contact models,such as the GW and MB models,but the majority of previous validations have been performed under light loads,resulting in a linear relationship between normal force an... Many experiments have supported the contact models,such as the GW and MB models,but the majority of previous validations have been performed under light loads,resulting in a linear relationship between normal force and contact area.However,the real contact area fraction should never equal one;there must be a limit smaller than the apparent area,implying that the real contact area cannot increase linearly indefinitely.In this paper,the real contact area between two polymethylmethacrylate(PMMA)blocks under heavy load is measured using the total reflection method,and the contact area is analyzed using the image processing method.The results show that the real contact area increases with normal load linearly in light loads but non-linearly in heavy loads;the number of contact spots increases with load linearly in light loads but also non-linearly in heavy loads,synchronous with the change in the real contact area.The GW,MB,and Zhao,Maietta,and Chang(ZMC)models were used to predict the experiment results,but none of them predicted the non-linear stage.A revised GW model based on the bulk deformation hypothesis performs better in predicting the non-linear stage.The study’s findings can be applied to PMMA or other similar materials,and they can serve as a useful reference for future research on the contact mechanisms of other materials. 展开更多
关键词 Real contact area GW model MB model Total reflection non-linear increase
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Sexually differentiated decision-making involves faster recruitment in the early stages for the Tibetan antelopes Pantholops hodgsonii
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作者 Qin Zhu Jian Guan +6 位作者 Tianya Lei Kun Xuan Sile Guo Yumeng Zhao Changjian Fu Le Yang Zhongqiu Li 《Current Zoology》 2025年第1期124-135,共12页
Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studie... Group living is widespread across diverse taxa,and the mechanisms underlying collective decision-making in contexts of variable role division are critical for understanding the dynamics of group stability.While studies on collective behavior in small animals such as fish and insects are well-established,similar research on large wild animals remains challenging due to the limited availability of sufficient and systematic field data.Here,we aimed to explore the collective decision-making pattern and its sexual difference for the dimorphic Tibetan antelopes Pantholops hodgsonii(chiru)in Xizang Autonomous Region,China,by analyzing individual leadership distribution,as well as the joining process,considering factors such as calving stages and joining ranks.The distinct correlations of decision participants’ratio with group size and decision duration underscore the trade-off between accuracy and speed in decision-making.Male antelopes display a more democratic decision-making pattern,while females exhibit more prompt responses after calving at an early stage.This study uncovers a partially shared decision-making strategy among Tibetan antelopes,suggesting flexible self-organization in group decision processes aligned with animal life cycle progression. 展开更多
关键词 calving stage DECISION-MAKING LEADERSHIP sexual differences Tibetan antelopes
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Efficacy of adjuvant chemotherapy in stage II colon cancer patients with twelve or more lymph nodes retrieve
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作者 Yu Huo Yue-Yang Zhang +4 位作者 Shuai Jiao Zhong-Yuan Bai Wen-Qi Bai Hai-Tao Zhou Xu Guan 《World Journal of Gastrointestinal Oncology》 2025年第9期110-120,共11页
BACKGROUND The National Comprehensive Cancer Network guidelines recommend adjuvant chemotherapy(ACT)for patients with stage II colon cancer who have undergone curative surgery when fewer than 12 lymph nodes(LNs)are re... BACKGROUND The National Comprehensive Cancer Network guidelines recommend adjuvant chemotherapy(ACT)for patients with stage II colon cancer who have undergone curative surgery when fewer than 12 lymph nodes(LNs)are retrieved.This study seeks to further examine the requirement for ACT in individuals who had 12 or more LNs harvested.AIM To investigate if stage II colon cancer patients with 12 or more LNs retrieved benefit from ACT.METHODS This retrospective cohort study included individuals diagnosed with stage II colon cancer who underwent surgery between 2008 and 2017 from the Surveillance,Epidemiology,and End Results(SEER)registry and a Chinese multicenter database.All patients had at least 12 LNs retrieved.The key endpoint was overall survival(OS).Cox regression analysis was performed to assess independent OS predictors.Propensity score matching controlled for confounders,and Kaplan-Meier analysis evaluated the impact of ACT on survival.RESULTS A total of 32742 patients with stage II colon cancer from the SEER cohort and 3153 patients from the Chinese cohort were included.The average number of LNs retrieved was 20.0(15.0,26.0)in the SEER cohort and 18.0(15.0,22.0)in the Chinese cohort.No-ACT remained an independent risk factor in both cohorts(hazard ratio=1.589,95%confidence interval:1.485-1.700 and hazard ratio=1.865,95%confidence interval:1.465-2.375,respectively).In the SEER cohort,patients in the ACT group consistently demonstrated better 5-year OS rates both before and after propensity score matching(79.4%vs 66.1%and 79.4%vs 69.4%,both P<0.0001).Similarly,these findings were further validated in the Chinese cohort(91.2%vs 82.1%and 90.0%vs 82.8%,both P<0.0001).ACT improved prognosis even in T3 and grade 1/2 patients.CONCLUSION This research,based on two large population-based cohorts,demonstrates that stage II colon cancer patients with 12 or more LNs retrieved can still benefit from ACT. 展开更多
关键词 stage II Colon cancer Lymph nodes CHEMOTHERAPY PROGNOSIS
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Application of the modified Byars staged procedure for severe hypospadias repair
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作者 Qi-Gen Xie Ting-Ting Xue +4 位作者 Xu-Ren Chen Zhao-Ying Li Zhe Xu Zuo-Qing Li Peng Luo 《Asian Journal of Andrology》 2025年第1期65-71,共7页
This study aimed to introduce a modified Byars staged procedure and investigate its application value in patients with severe hypospadias.We retrospectively analyzed the clinical data of patients with severe hypospadi... This study aimed to introduce a modified Byars staged procedure and investigate its application value in patients with severe hypospadias.We retrospectively analyzed the clinical data of patients with severe hypospadias admitted to the First Affiliated Hospital of Sun Yat-sen University(Guangzhou,China)between October 2012 and October 2022.In total,31 patients underwent the conventional Byars procedure(conventional group),and 45 patients underwent the modified Byars staged procedure(modified group).Our modified strategy was built upon the standard Byars procedure by incorporating glansplasty during the first stage and employing a Y-shaped flap in conjunction with a glandular tunnel for urethroplasty during the second stage.Notably,there were no statistically significant differences in the preoperative baseline characteristics,duration of surgery,amount of blood loss,or occurrence of postoperative complications,including urethral fistula,stricture and diverticulum,or penile curvature,between the conventional and modified groups.However,there was a significantly lower incidence of coronal sulcus fistula(0 vs 16.1%,P=0.02)and glans dehiscence(0 vs 12.9%,P=0.02)in the surgical group than that in the conventional group.In addition,the modified group exhibited a notably greater rate of normotopic urethral opening(100.0%vs 83.9%,P=0.01)and a higher mean score on the Hypospadias Objective Penile Evaluation(HOPE;mean±standard error of mean:8.6±0.2 vs 7.9±0.3,P=0.02)than did the conventional group.In conclusion,the modified Byars staged procedure significantly reduced the risks of glans dehiscence and coronal sulcus fistula.Consequently,it offers a promising approach for achieving favorable penile esthetics,thereby providing a reliable therapeutic option for severe hypospadias. 展开更多
关键词 byars glans dehiscence severe hypospadias staged procedure TUNNEL URETHROPLASTY
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Research on Risk Management in the Decision- Making Stage of a Project Based on DPSIR
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作者 Yujie Zhang 《Proceedings of Business and Economic Studies》 2025年第1期28-37,共10页
With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can great... With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can greatly enhance project management efficiency.This paper integrates the AHP-entropy value method and constructs a risk management model based on the DPSIR framework for construction projects.The model is applied to evaluate and analyze the risk level of the decision-making stage in a navigation and electricity hub project in Chongqing Municipality.The results demonstrate the scientific validity and effectiveness of the proposed model. 展开更多
关键词 DPSIR Construction projects Decision stage Risk management AHP-entropy method
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Buckling morphology evolution of thin films on non-linear elastic substrates
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作者 Andi Lai Di Ou +1 位作者 Jun Liao Guo Fu 《Acta Mechanica Sinica》 2025年第2期176-183,共8页
Organisms have evolved a strain limiting mechanism,reflected as a non-linear elastic constitutive,to prevent large deformations from threatening soft tissue integrity.Compared with linear elastic substrates,the wrinkl... Organisms have evolved a strain limiting mechanism,reflected as a non-linear elastic constitutive,to prevent large deformations from threatening soft tissue integrity.Compared with linear elastic substrates,the wrinkle of films on non-linear elastic substrates has received less attention.In this article,a unique wrinkle evolution of the film-substrate system with a J-shaped non-linear stress-strain relation is reported.The result shows that a concave hexagonal array pattern is formed with the shrinkage strain of the film-substrate systems developing.As the interconnection of hexagonal arrays,a unit cell ridge network appears with properties such as chirality and helix.The subparagraph maze pattern formed with high compression is mainly composed of special single-cell ridge networks such as spiral single cores,chiral double cores,and combined multi-cores.This evolutionary model is highly consistent with the results of experiments,and it also predicts wrinkle morphology that has not yet been reported.These findings can serve as a novel explanation for the surface wrinkle of biological soft tissue,as well as provide references for the preparation of artificial biomaterials and programmable soft matter. 展开更多
关键词 non-linear elastic substrate Chiral ridge Spiral unit cell Tension-compression asymmetry Wrinkle morphological evolution
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Research on the estimation of wheat AGB at the entire growth stage based on improved convolutional features
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作者 Tao Liu Jianliang Wang +7 位作者 Jiayi Wang Yuanyuan Zhao Hui Wang Weijun Zhang Zhaosheng Yao Shengping Liu Xiaochun Zhong Chengming Sun 《Journal of Integrative Agriculture》 2025年第4期1403-1423,共21页
The wheat above-ground biomass(AGB)is an important index that shows the life activity of vegetation,which is of great significance for wheat growth monitoring and yield prediction.Traditional biomass estimation method... The wheat above-ground biomass(AGB)is an important index that shows the life activity of vegetation,which is of great significance for wheat growth monitoring and yield prediction.Traditional biomass estimation methods specifically include sample surveys and harvesting statistics.Although these methods have high estimation accuracy,they are time-consuming,destructive,and difficult to implement to monitor the biomass at a large scale.The main objective of this study is to optimize the traditional remote sensing methods to estimate the wheat AGBbased on improved convolutional features(CFs).Low-cost unmanned aerial vehicles(UAV)were used as the main data acquisition equipment.This study acquired image data acquired by RGB camera(RGB)and multi-spectral(MS)image data of the wheat population canopy for two wheat varieties and five key growth stages.Then,field measurements were conducted to obtain the actual wheat biomass data for validation.Based on the remote sensing indices(RSIs),structural features(SFs),and CFs,this study proposed a new feature named AUR-50(multi-source combination based on convolutional feature optimization)to estimate the wheat AGB.The results show that AUR-50 could estimate the wheat AGB more accurately than RSIs and SFs,and the average R^(2) exceeded 0.77.In the overwintering period,AUR-50_(MS)(multi-source combination with convolutional feature optimization using multispectral imagery)had the highest estimation accuracy(R^(2) of 0.88).In addition,AUR-50 reduced the effect of the vegetation index saturation on the biomass estimation accuracy by adding CFs,where the highest R^(2) was 0.69 at the flowering stage.The results of this study provide an effective method to evaluate the AGB in wheat with high throughput and a research reference for the phenotypic parameters of other crops. 展开更多
关键词 WHEAT above-ground biomass UAV entire growth stage convolutional feature
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Staged dendrite suppression for high safe and stable lithium-sulfur batteries
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作者 Jun Jiang Zhenjie Lu +12 位作者 Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu 《Journal of Energy Chemistry》 2025年第1期674-683,共10页
The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithiu... The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur batteries.Herein,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene (PP) separator.The uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition stage.Most importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance(145.88 MPa) of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium dendrite.The Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm^(-2)with a polarization voltage of only 29.3 mV.Additionally,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity attenuation.The improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect. 展开更多
关键词 Lithium-sulfur batteries staged dendrite suppression Shuttle effect Surface-negatively-charged nanodiamond
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Design of mobile stage location system based on two-dimensional laser radar
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作者 WANG Bo ZHU Ping +1 位作者 ZHENG Qingsong YANG Jiaqi 《High Technology Letters》 2025年第1期20-31,共12页
This paper addresses the design problem of an embedded mobile stage location system based on a two-dimensional laser radar.The mobile stage is a piece of important performance equipment in art performances,and the pos... This paper addresses the design problem of an embedded mobile stage location system based on a two-dimensional laser radar.The mobile stage is a piece of important performance equipment in art performances,and the positioning problem is one of the key issues in the control of the mobile stage.Both hardware and software are developed for the mobile stage.The hardware of the location system consists of a laser radar,an embedded control board,a wireless router,and a motion control unit.The software of the location system includes embedded software and human-machine interface(HMI),and they are designed to achieve the functions of real-time positioning and monitoring.First,a novel landmark identification method is presented based on the landmark reflection intensities and shapes.Then,the initial pose of the mobile stage is calculated by using the triangle matching algorithm and the least squares method.A distributed fusion Kalman filtering algorithm is applied to fuse landmark information and odometer information to achieve real-time positioning of the mobile stage.The designed system has been implemented in a practical mobile stage,and the results demonstrate that the location system can achieve a high positioning precision in both the stationary and moving scenarios. 展开更多
关键词 mobile stage positioning laser radar Kalman filter distributed fusion
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Transcriptomic profiling of cardiac development in Bama Xiang pigs across key developmental stages
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作者 Sheng-Nan Wang Wen-Jie Tian +4 位作者 Deng-Ke Pan Tang Hai Yue-Hui Ma Dan-Dan Wang Lin Jiang 《Zoological Research》 2025年第3期634-646,共13页
Pigs have emerged as valuable large-animal models for cardiac xenotransplantation;however,the temporal dynamics of myocardial development in this species remains insufficiently defined.This study analyzed gene express... Pigs have emerged as valuable large-animal models for cardiac xenotransplantation;however,the temporal dynamics of myocardial development in this species remains insufficiently defined.This study analyzed gene expression patterns across four key developmental stages(neonatal,juvenile,sexual maturity,and adulthood)to delineate the molecular mechanisms driving porcine myocardial development.Increases in heart weight were accompanied by proportional expansion of myocardial fiber area and chamber size,reflecting coordinated structural development.Transcriptomic profiling of myocardial tissue by RNA sequencing(RNA-seq)identified 2189 differentially expressed genes(DEGs)across stage comparisons.Short time-series expression miner(STEM)analysis classified these DEGs into four major expression clusters enriched in pathways associated with myocardial development,immune responses,cell proliferation,and metabolic processes.Among 359 DEGs conserved across all developmental stages,six candidate genes were strongly associated with myocardial development.Reverse transcription-quantitative real-time polymerase chain reaction(RT-qPCR)confirmed a significant correlation between the expression of these candidate genes and myocardial development in porcine tissue.These findings establish a transcriptomic framework for porcine myocardial maturation and provide a molecular basis for advancing cardiac xenotransplantation. 展开更多
关键词 Cardiac tissue Bama Xiang pig Multiple stages Heart development TRANSCRIPTOMICS
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Nonlinear effect analysis and compensation based on improved friction observer for torque rotating stage
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作者 Yingjie Jia Bo Liu +1 位作者 Hui Tang Yuzhang Wei 《Nanotechnology and Precision Engineering》 2025年第3期138-148,共11页
In semiconductor precision packaging and other applications involving alignment of automated equipment,the nonlinear motion caused by structural characteristics and friction effects on torque-type rotating motion stag... In semiconductor precision packaging and other applications involving alignment of automated equipment,the nonlinear motion caused by structural characteristics and friction effects on torque-type rotating motion stages seriously affects output accuracy and stability.To solve this problem,the motion characteristics of a rotating stage and the mechanism by which friction nonlinearity influences accuracy are analyzed in detail.In addition,a compound control strategy based on a kinematic model and the Stribeck friction model is designed.A friction disturbance observer based on output position feedback is improved for simple parameter tuning.Finally,an experimental system is constructed to carry out validation tests,including identification of nonlinear characteristics and performance comparisons.The experimental results show that the linear tracking error of the torque-type rotating stage is less than 1.47µm after adoption of the proposed model-based composite control strategy,and the corresponding rotary angle deviation is less than 0.0153°.The linearity of output motion is increased to 97.59%and the error compensation effect is improved by 51.6%compared with the PID control method.The experimental results confirm that the analysis method adopted here and the proposed compensation strategy can effectively reduce frictional nonlinearity and improve motion accuracy.The proposed method can also be applied to other precision electromechanical systems. 展开更多
关键词 Rotating stage Mechanical analysis Frictional nonlinear effect Disturbance observation
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Effectiveness of nulliparous women’s different childbirth positions during the second stage of labor:A systematic review and network meta-analysis
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作者 Hongyan Liu Lingling Li +5 位作者 Xiaojiao Wang Xinli Zhu Liping Sun Chunxiang Zhu Hui Min Chunyi Gu 《International Journal of Nursing Sciences》 2025年第3期268-275,共8页
Objectives A systematic review and network meta-analysis was conducted to evaluate the effectiveness of different childbirth positions in reducing the duration of the second stage of labor,providing evidence-based ins... Objectives A systematic review and network meta-analysis was conducted to evaluate the effectiveness of different childbirth positions in reducing the duration of the second stage of labor,providing evidence-based insights for obstetric institutions to guide interventions related to childbirth positions.Methods A comprehensive literature search was conducted in databases,including PubMed,Web of Science,the Cochrane Library,Embase,Wanfang Databases,China National Knowledge Infrastructure Databases(CNKI),China Science and Technology Journal Database(CSTJ),and China Biology Medicine disc(CBMdisc)to identify studies on the effectiveness of different childbirth positions in reducing the duration of the second stage of labor.The search included randomized controlled trials published from database inception to September 30,2024.The Cochrane risk-of-bias tool was used to assess the quality of the studies.Two independent reviewers screened the literature,extracted data,and evaluated study quality.Subsequently,a network meta-analysis was performed using STATA software.The study protocol has been registered in PROSPERO(CRD42023428217).Results This study analyzed data from 25 randomized controlled trials involving 9,844 women.The findings indicated that in comparison to lithotomy position,free position(MD=20.53,95%CI[11.38,29.68])and upright position(MD=−24.13,95%CI[−42.94,-5.32])were found to be superior in reducing the duration of the second stage of labor.Free position outperformed kneeling position(MD=21.48,95%CI[4.67,38.28])and squatting position(MD=23.43,95%CI[1.88,44.97]);upright position was superior to kneeling position(MD=−25.08,95%CI[−46.93,−3.22]);semirecumbent position surpassed squatting position(MD=19.71,95%CI[2.05,37.38]);and upright position was also superior to squatting position(MD=−27.03,95%CI[−51.48,−2.57]).According to the surface under the cumulative ranking curve(SUCRA),the upright position emerged as the most effective for reducing the duration of the second stage of labor(87.4%),followed by free position(81.1%),semirecumbent position(70.0%),and lateral position(62.3%).Conclusion These findings offer valuable insights for midwifery practice and help inform future research directions.Considering the limitations of this review,more larger-scale,multicenter randomized controlled trials are warranted to further evaluate the relative effectiveness of different childbirth positions in reducing the duration of the second stage of labor. 展开更多
关键词 CHILDBIRTH POSITION Nulliparous women Network meta-analysis Second stage of labor
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