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基于VMD-T2V-Transformer的太阳辐射预测
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作者 胡雅彬 史加荣 +1 位作者 陈应瑞 雍龙泉 《太阳能学报》 北大核心 2025年第7期778-784,共7页
太阳辐射的不确定性导致太阳能发电具有明显的随机性和不稳定性。针对此问题,该文结合变分模态分解(VMD)、Time2Vec(T2V)和Transformer,提出一种用于太阳辐射预测的VMD-T2V-Transformer模型。首先利用VMD将太阳辐射序列分解为若干子序列... 太阳辐射的不确定性导致太阳能发电具有明显的随机性和不稳定性。针对此问题,该文结合变分模态分解(VMD)、Time2Vec(T2V)和Transformer,提出一种用于太阳辐射预测的VMD-T2V-Transformer模型。首先利用VMD将太阳辐射序列分解为若干子序列;接着采用T2V对分解后的每个子序列进行时间特征嵌入;然后对嵌入时间特征后的子序列建立Transformer预测模型;最后将各模型的预测结果进行叠加,得到最终预测值。实验结果表明:该文所提模型优于其他主流模型,RMSE和MAE至少降低13.81%和16.44%。 展开更多
关键词 太阳辐射 太阳能发电 变分模态分解 Time2Vec transformER
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特征融合的MV2-Transformer肺炎X光图像分类模型
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作者 平金如 孙子文 《计算机应用》 北大核心 2025年第12期4030-4036,共7页
针对肺炎X光图像病灶区域特征难以被提取和现有模型轻量化程度不高的问题,提出一种特征融合的MV2-Transformer(FFMV2-Transformer)肺炎X光图像分类模型。首先,采用轻量型网络MobileNetV2(Mobile Network Version 2)作为主干网络,并在反... 针对肺炎X光图像病灶区域特征难以被提取和现有模型轻量化程度不高的问题,提出一种特征融合的MV2-Transformer(FFMV2-Transformer)肺炎X光图像分类模型。首先,采用轻量型网络MobileNetV2(Mobile Network Version 2)作为主干网络,并在反向残差瓶颈块中嵌入坐标注意力(CA)机制,从而通过将位置信息嵌入通道信息提高模型对病灶区域特征的提取能力;其次,设计局部和全局特征融合模块(LGFFM)将卷积层提取的局部特征与Transformer捕获的全局特征相结合,从而使模型能同时捕捉病灶区域的细节信息和整体信息,并进一步提高模型的语义特征提取能力;最后,设计跨层特征融合模块(CFFM)将空间注意力机制增强的浅层特征的空间信息与通道注意力机制增强的深层特征的语义信息相结合,从而获得丰富的上下文信息。为了验证模型的有效性,在肺炎X光数据集上进行消融实验和对比实验,结果表明,FFMV2-Transformer模型与MobileViT(Mobile Vision Transformer)模型相比,准确率、精确率、召回率、F1值和AUC(Area Under ROC(Receiver Operating Characteristic)Curve)值分别提高了1.09、0.31、1.91、1.08和0.40个百分点。可见,FFMV2-Transformer模型能在实现模型轻量化的同时,有效提取肺炎X光图像病灶区域的特征。 展开更多
关键词 肺炎X光图像 注意力机制 MobileNetV2 transformER 特征融合
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融合SOLOv2-Vision Transformer的面瘫识别方法研究
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作者 庄哲笼 丁有伟 +2 位作者 胡孔法 陈科宏 陈功 《南京中医药大学学报》 北大核心 2025年第10期1399-1406,共8页
目的为了使患者和医生更快诊断病情,达到早发现、早诊断、早治疗的目的,建立准确及时的面瘫智能化辅助诊断方法。方法提出融合SOLOv2-Vision Transformer的方法,将收集的面瘫数据经过替换主干网络的SOLOv2模型分割,去除图像中干扰部分,... 目的为了使患者和医生更快诊断病情,达到早发现、早诊断、早治疗的目的,建立准确及时的面瘫智能化辅助诊断方法。方法提出融合SOLOv2-Vision Transformer的方法,将收集的面瘫数据经过替换主干网络的SOLOv2模型分割,去除图像中干扰部分,再输入到Vision Transformer模型中进行分类训练。通过先分割再分类的原则,提高面瘫图像的分类效果。结果该实验方法在MEEI面瘫数据集上的准确率为0.982、召回率为0.982、F1-score为0.981,相比于基础模型分别提高了2%、4%、4%。结论融合SOLOv2-Vision Transformer的面瘫分类模型,相比较于未经分割的方法可实现更高的识别精度,为面瘫诊断提供了新方法。 展开更多
关键词 图像分割 图像分类 注意力机制 面瘫 诊断 SOLOv2-Vision transformer
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Transformation behavior of calcium vanadate and manganese vanadate in CaO-V_(2)O_(5)-MnO_(2) system during calcification roasting of vanadium slag 被引量:1
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作者 Jing WEN Tao JIANG +2 位作者 Fei-fei LI Tang-xia YU Bo-jian CHEN 《Transactions of Nonferrous Metals Society of China》 2025年第6期2049-2060,共12页
A simplified CaO-V_(2)O_(5)-MnO_(2) system was established to qualitatively and quantitatively investigate the transformation behavior of vanadates.The results demonstrated dynamic transformations between calcium vana... A simplified CaO-V_(2)O_(5)-MnO_(2) system was established to qualitatively and quantitatively investigate the transformation behavior of vanadates.The results demonstrated dynamic transformations between calcium vanadate and manganese vanadate as n(CaO)/n(V_(2)O_(5))/n(MnO_(2))ratios and roasting temperatures varied.When MnO_(2) was incrementally added with n(CaO)/n(V_(2)O_(5))of 2,some Ca_(2)V_(2)O_(7) converted to Mn_(2)V_(2)O_(7).The mass of vanadium as calcium vanadate consistently exceeded that as manganese vanadate.Conversely,when CaO was gradually added with n(MnO_(2))/n(V_(2)O_(5))of 2,Mn_(2)V_(2)O_(7) tended to transform into Ca_(2)V_(2)O_(7) and Ca3V2O8.The affinity of vanadium for calcium was higher compared that of vanadium for manganese.The specific type of calcium vanadate formed depended on both n(CaO)/n(V_(2)O_(5))/n(MnO_(2))values and roasting temperatures,while manganese vanadate remained predominantly as Mn_(2)V_(2)O_(7).The influence of roasting temperature on the conversion between calcium vanadate and manganese vanadate was minimal.At n(CaO)/n(V_(2)O_(5))/n(MnO_(2))of 2/1/2 and temperatures ranging from 650 to 850°C,the mass ratio of vanadium present as calcium vanadate to manganese vanadate stabilized at approximately 2. 展开更多
关键词 transformation behavior CaO−V_(2)O_(5)−MnO_(2) calcium vanadate manganese vanadate vanadium slag calcification roasting
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Fast phase transformation of micrometer-scale single-crystal TiNb_(2)O_(7)anode for Ah-level fast-charging laminated pouch cell
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作者 Renming Zhan Shiyu Liu +9 位作者 Hongyu Luo Zhengxu Chen Yangtao Ou Wenyu Wang Tianqi Chai Xiancheng Wang Shuibin Tu Zihe Chen Xiaoxue Chen Yongming Sun 《Journal of Energy Chemistry》 2025年第9期685-693,I0018,共10页
The Wadsley-Roth phase TiNb_(2)O_(7)(TNO)has been identified as a promising anode material with potential for high safety and fast-charging lithium-ion batteries(LIBs),arising from its competitive theoretical specific... The Wadsley-Roth phase TiNb_(2)O_(7)(TNO)has been identified as a promising anode material with potential for high safety and fast-charging lithium-ion batteries(LIBs),arising from its competitive theoretical specific capacity and secure operational potential.Despite the significant advancements in specific capacity,fast charging,and longevity at the coin cell level,a comprehensive understanding and realization of the fast-charging capability and corresponding cycling stability of the TNO under practical application conditions(such as a pouch cell with an anode capacity exceeding 2 mAh cm^(-2))continues to be elusive.In this study,we explore a simple,scalable solid-phase carbon source melt strategy to fabricate the kilogram-level micrometer-scale single-crystal TNO particles enveloped by an ultrathin carbon coating layer of<5 nm(TNO@C).The in-situ X-ray diffraction(XRD)measurement of the LiCoO_(2)‖TNO@C laminated pouch cell(anode mass loading of~10 mg cm^(-2))under fast charging/discharging conditions with the combination of material characterizations and electrochemical analysis reveals a fast,yet stable crystal structure evolution for the micrometer-scale single-crystal TNO@C with only 7.03%fluctuation in unit cell volume value,which is indicative of fast reaction kinetics.The Ah-level laminated LiCoO_(2)‖TNO@C pouch cell achieved 80.8%charge within 6 min(10 C)and retained 85.3%capacity after 1000 cycles at the charging current density of 6 C(10 min),far surpassing all the results in previous publications.The straightforward synthetic approach for the micrometer-scale single-crystal TNO@C,coupled with a clear understanding of reaction kinetics and rapid crystal structure evolution,paves the way for the practical application of the micrometer-scale single-crystal TNO@C anode material for fast charging LIBs. 展开更多
关键词 TiNb_(2)O_(7) Phase transformation Electrochemical reaction kinetics Fast charging Lithium-ion batteries
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Mobility-Aware Edge Caching with Transformer-DQN in D2D-Enabled Heterogeneous Networks
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作者 Yiming Guo Hongyu Ma 《Computers, Materials & Continua》 2025年第11期3485-3505,共21页
In dynamic 5G network environments,user mobility and heterogeneous network topologies pose dual challenges to the effort of improving performance of mobile edge caching.Existing studies often overlook the dynamic natu... In dynamic 5G network environments,user mobility and heterogeneous network topologies pose dual challenges to the effort of improving performance of mobile edge caching.Existing studies often overlook the dynamic nature of user locations and the potential of device-to-device(D2D)cooperative caching,limiting the reduction of transmission latency.To address this issue,this paper proposes a joint optimization scheme for edge caching that integrates user mobility prediction with deep reinforcement learning.First,a Transformer-based geolocation prediction model is designed,leveraging multi-head attention mechanisms to capture correlations in historical user trajectories for accurate future location prediction.Then,within a three-tier heterogeneous network,we formulate a latency minimization problem under a D2D cooperative caching architecture and develop a mobility-aware Deep Q-Network(DQN)caching strategy.This strategy takes predicted location information as state input and dynamically adjusts the content distribution across small base stations(SBSs)andmobile users(MUs)to reduce end-to-end delay inmulti-hop content retrieval.Simulation results show that the proposed DQN-based method outperforms other baseline strategies across variousmetrics,achieving a 17.2%reduction in transmission delay compared to DQNmethods withoutmobility integration,thus validating the effectiveness of the joint optimization of location prediction and caching decisions. 展开更多
关键词 Mobile edge caching D2D heterogeneous networks deep reinforcement learning transformer model transmission delay optimization
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Enhancing strength-ductility synergy in L1_(2)-strengthened high-entropy alloys via microband and transformation induced plasticity
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作者 Hongchao Li Jun Wang +5 位作者 Huihui Zhi Jiawang Zhao Zicheng Cai Mengmeng Zhao William Yi Wang Jinshan Li 《Journal of Materials Science & Technology》 2025年第12期86-98,共13页
Precipitation–strengthened high entropy alloys (HEAs) exhibit excellent strength–ductility combinations due to precipitation hindering dislocation gliding and work hardening ability of the matrix. However, the effec... Precipitation–strengthened high entropy alloys (HEAs) exhibit excellent strength–ductility combinations due to precipitation hindering dislocation gliding and work hardening ability of the matrix. However, the effect of compositions on the microstructure and related deformation mechanism of HEAs is still unclear. In this study, we developed two types of L1_(2)–strengthened Al_(5)Ti_(8)Fe_(x)(CoNi)_(86.9–x)B_(0.1) (x = 17, 28) HEAs to study the effect of Fe content on the deformation mechanism. Our results reveal that an increased Fe concentration substantially increases the strength and ductility of Al_(5)Ti_(8)Fe_(x)(CoNi)_(86.9–x)B_(0.1) HEAs at room temperature. For the Al_(5)Ti_(8)Fe17(CoNi)_(69.9)B_(0.1) HEA, the presence of a large amount of ordered L1_(2) phase leads to strain strengthening governed by dynamically refined slip bands. For the Al_(5)Ti_(8)Fe28(CoNi)58.9B_(0.1) HEA, the increasing Fe content raises the stacking fault energy of the matrix and reduces the stability of the FCC matrix, making it less stable than the BCC structure. Additionally, the reduced volume fraction of the ordered L1_(2) precipitated phase and the increased stack fault energy of the FCC matrix lead to an increase in the cross-slip frequency during deformation, which in turn promotes avalanche glide of dislocations on highly stressed crystallographic slip planes and the generation of microbands. The microbands and phase transformation inside the microbands promote the strain strengthening, resulting in enhanced strength and ductility. These findings clarify the effect of the Fe content on the deformation behaviours and provide new insight into the formation mechanism of microbands in precipitation-strengthened HEAs, which will open new avenues for the design of ultra-strong yet ductile alloys in the future. 展开更多
关键词 L1_(2)-strengthened High-entropy alloys Fe content Microband-induced plasticity FCC→BCC transformation
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Open-Ocean Shallow-Water Dynamics via a(2+1)-Dimensional Generalized Variable-Coefficient Hirota-Satsuma-Ito System: Oceanic Auto-B?cklund Transformation and Oceanic Solitons
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作者 GAO Xin-yi 《China Ocean Engineering》 2025年第3期541-547,共7页
Recently, during the investigations on planetary oceans, Hirota-Satsuma-Ito-type models have been developed. In this paper, for a(2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system describing ... Recently, during the investigations on planetary oceans, Hirota-Satsuma-Ito-type models have been developed. In this paper, for a(2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system describing the fluid dynamics of shallow-water waves in an open ocean, non-characteristic movable singular manifold and symbolic computation enable an oceanic auto-B?cklund transformation with three sets of the oceanic solitonic solutions. The results rely on the oceanic variable coefficients in that system. Future oceanic observations might detect some nonlinear features predicted in this paper, and relevant oceanographic insights might be expected. 展开更多
关键词 OCEAN shallow water (2+1)-dimensional generalized variable-coefficient Hirota-Satsuma-Ito system singular manifold symbolic computation B?cklund transformation soliton
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Migration and morphological transformation of Mn^(2+)and its effect on microbial community in the A^(2)O process
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作者 Xiaohui Xu Jiexiong Zhong +4 位作者 Xinyao Hao Qun Liu Min Lu Xiaohui Guan Lanhe Zhang 《Journal of Environmental Sciences》 2025年第11期404-416,共13页
Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the ... Manganese ion(Mn^(2+))was generated from metallurgical,steel making and chemical industries.It could affect microbial activity and community structure after entering sewage treatment plant.The effect of Mn^(2+)on the pollutant removal,metal distribution patterns and composition of microbial communities were investigated in a an anaerobic/anoxic/oxic(A^(2)O)process.The results showed that when Mn^(2+)concentration was 5 mg/L,the efficiencies for the removal of chemical oxygen demand(COD),total nitrogen(TN)and total phosphorus(TP)attained remarkable levels of 96%,93%,and 99%,respectively.In the sludge,the distribution pattern of Mn^(2+)concentration was tightly bound extracellular polymeric substances(TB-EPS)>supernatant>loosely bound EPS(LB-EPS)>soluble microbial products(SMP).Mn^(2+)was found to enrich and accumulate in the microorganism cells.In addition,Mn^(2+)was mainly found in residual fractions and reducible fractions of pellet that manganese was present.The pellet was discovered to contain a substantial quantity of manganese,which was present in various oxidation states,including Mn^(4+),Mn^(3+)and Mn^(2+).The escalating levels of Mn^(2+)led to a reduction in the richness and diversity of microbial communities inhabiting various regions of the A^(2)O reactor.Nonetheless,the uniformity experienced only subtle alterations.Proteobacteria and Bacteroidetes emerged as the leading phyla within the microbial ecosystem,experiencing a steady rise in their respective proportions.The dominant bacterial groups,Azospira and Dechromonas,experienced an incremental increase in their relative prevalence,which played a constructive role in the process of pollutant removal. 展开更多
关键词 Manganese ion Anaerobic/anoxic/oxic(A^(2)O)reactor Migration and transformation Morphology Microbial community
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Biological Features of KLC2 Mutations in Chronic Myeloid Leukemia and Their Contribution to Inducing Drug Resistance
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作者 Rabindranath Bera Yotaro Ochi +4 位作者 Ying-Jung Huang Ming-Chung Kuo Kenichi Yoshida Seishi Ogawa Lee-Yung Shih 《Oncology Research》 2026年第1期202-221,共20页
Background:Breakpoint Cluster Region-Abelson(BCR::ABL1)fusion protein is essential in the pathogenesis of chronic myeloid leukemia(CML);however,the chronic-to-blast phase transformation remains elusive.We identified n... Background:Breakpoint Cluster Region-Abelson(BCR::ABL1)fusion protein is essential in the pathogenesis of chronic myeloid leukemia(CML);however,the chronic-to-blast phase transformation remains elusive.We identified novel kinesin light chain 2(KLC2)mutations in CML-myeloid blast phase patients.We aimed to examine the functional role of KLC2 mutations in leukemogenesis.Methods:To evaluate the biological role of KLC2 mutants(MT)in CML cells,we expressed KLC2-MT in different human CML cell lines harboring BCR::ABL1 and performed immunoblot,immunofluorescence,cell proliferation,differentiation,and apoptosis;Tyrosine kinase inhibitor(TKI)-drug activities;and clonogenic assays for in vitro functional analyses.We co-expressed KLC2-MT and BCR::ABL1 in mouse bone marrow cells(BMCs)to evaluate their clonogenic and self-renewal abilities ex vivo.Furthermore,we examined tumorigenic activity and drug efficacy in the K562 xenograft model.Results:KLC2-MT overexpression in BCR::ABL1-positive K562 and KU812 CML cells promoted cell proliferation and clonogenic potential,decreased imatinib sensitivity,and reduced apoptosis.Serial colony replating assays revealed that KLC2-MT and BCR::ABL1 co-expression enhanced the self-renewal ability of mouse BMCs with immature morphology.In the K562 xenograft model,KLC2-MT enhanced tumorigenic potential and diminished imatinib efficacy.Further studies reported that KLC2-MT augmented signal transducer and activator of transcription 3(STAT3)activation and nuclear accumulation in imatinib-treated CML cells.KLC2-WT and KLC2-MT interacted with mothers against decapentaplegic homolog 2(SMAD2);however,the latter impaired transforming growth factor-beta(TGF-β)–mediated SMAD2/3 activation while enhancing STAT3 phosphorylation.Conclusions:This study demonstrates the biological and functional importance of KLC2 mutation in CML cells,potentially enabling the development of better treatment strategies for CML patients carrying KLC2 mutations and providing enhanced understanding of the disease progression. 展开更多
关键词 Chronic myeloid leukemia(CML) kinesin light chain 2(KLC2) signal transducer and activator of transcription 3(STAT3) drug resistance myeloid blast transformation
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Small extracellular vesicles derived from hair follicle neural crest stem cells enhance perineurial cell proliferation and migration via the TGF-β/SMAD/HAS2 pathway
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作者 Yiming Huo Bing Xiao +8 位作者 Haojie Yu Yang Xu Jiachen Zheng Chao Huang Ling Wang Haiyan Lin Jiajun Xu Pengfei Yang Fang Liu 《Neural Regeneration Research》 2026年第5期2060-2072,共13页
Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration vi... Peripheral nerve defect repair is a complex process that involves multiple cell types;perineurial cells play a pivotal role.Hair follicle neural crest stem cells promote perineurial cell proliferation and migration via paracrine signaling;however,their clinical applications are limited by potential risks such as tumorigenesis and xenogeneic immune rejection,which are similar to the risks associated with other stem cell transplantations.The present study therefore focuses on small extracellular vesicles derived from hair follicle neural crest stem cells,which preserve the bioactive properties of the parent cells while avoiding the transplantation-associated risks.In vitro,small extracellular vesicles derived from hair follicle neural crest stem cells significantly enhanced the proliferation,migration,tube formation,and barrier function of perineurial cells,and subsequently upregulated the expression of tight junction proteins.Furthermore,in a rat model of sciatic nerve defects bridged with silicon tubes,treatment with small extracellular vesicles derived from hair follicle neural crest stem cells resulted in higher tight junction protein expression in perineurial cells,thus facilitating neural tissue regeneration.At 10 weeks post-surgery,rats treated with small extracellular vesicles derived from hair follicle neural crest stem cells exhibited improved nerve function recovery and reduced muscle atrophy.Transcriptomic and micro RNA analyses revealed that small extracellular vesicles derived from hair follicle neural crest stem cells deliver mi R-21-5p,which inhibits mothers against decapentaplegic homolog 7 expression,thereby activating the transforming growth factor-β/mothers against decapentaplegic homolog signaling pathway and upregulating hyaluronan synthase 2 expression,and further enhancing tight junction protein expression.Together,our findings indicate that small extracellular vesicles derived from hair follicle neural crest stem cells promote the proliferation,migration,and tight junction protein formation of perineurial cells.These results provide new insights into peripheral nerve regeneration from the perspective of perineurial cells,and present a novel approach for the clinical treatment of peripheral nerve defects. 展开更多
关键词 hair follicle neural crest stem cells HAS2 MIGRATION miR-21-5p perineurial cells proliferation peripheral nerve injury SMAD7 small extracellular vesicles transforming growth factor-β/SMAD signaling pathway
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Effect of Na_2O on alumina leaching property and phase transformation of MgO-containing calcium aluminate slags 被引量:5
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作者 王波 孙会兰 +1 位作者 国栋 张学政 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2752-2757,共6页
In order to remove or reduce the negative effect of MgO in calcium aluminate slags, the method of adding Na2O into calcium aluminate slags was studied and its effect on leaching mechanism was also analyzed. The result... In order to remove or reduce the negative effect of MgO in calcium aluminate slags, the method of adding Na2O into calcium aluminate slags was studied and its effect on leaching mechanism was also analyzed. The results show that the alumina leaching efficiency of the calcium aluminate slag increases from 68.73% to 80.86% with Na2O content increasing from 0 to 4% when MgO content is 3%. The XRD results show that the quaternary compound C20A13M3S3 disappears when Na2O content increases to 4%. The addition of Na2O cannot remove the negative effect of MgO on leachability completely. XRD and EDS results indicate that Na2O can come into the lattice of 12CaO·7Al2O3 and promote the formation of 12CaO·7Al2O3 展开更多
关键词 calcium aluminate slag NA2O MgO phase transformation alumina leaching
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离腹寡毛果实蝇性别决定基因transformer 2及其在昆虫中的进化
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作者 刘桂清 万方浩 《环境昆虫学报》 CSCD 北大核心 2015年第4期742-751,共10页
对离腹寡毛果实蝇性别决定基因transformer 2(tra-2)进行多角度的进化分析,为研究离腹寡毛果实蝇性别决定分子机制奠定基础。通过PCR结合RACE技术克隆瓜实蝇Bactrocera cucurbitae同源transformer 2基因的c DNA全长和内含子序列,并对该... 对离腹寡毛果实蝇性别决定基因transformer 2(tra-2)进行多角度的进化分析,为研究离腹寡毛果实蝇性别决定分子机制奠定基础。通过PCR结合RACE技术克隆瓜实蝇Bactrocera cucurbitae同源transformer 2基因的c DNA全长和内含子序列,并对该基因进行序列和进化分析。克隆得到瓜实蝇tra-2基因c DNA全长1467 bp,开放读码框753 bp,编码250个氨基酸残基,Gen Bank登录号为KR056217。瓜实蝇tra-2基因与其他6种离腹寡毛果实蝇的基因结构相似,均包含8个外显子和7个内含子。7种离腹寡毛果实蝇与实蝇科的地中海实蝇和按实蝇、蝇科的家蝇和丽蝇科的铜绿蝇为单一起源,而果蝇Tra-2表现出明显的分异。分子进化分析结果表明tra-2基因核苷酸变异主要来源于同义变异,接受净化选择压力。本研究明确了瓜实蝇tra-2的c DNA和基因组DNA结构特征,离腹寡毛果实蝇tra-2蛋白高度保守,主要接受净化选择压力。 展开更多
关键词 离腹寡毛果实蝇 transformER 2 性别决定分子机制 进化分析
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埃及伊蚊性别决定基因 Transformer 2 的鉴定与表达分析 被引量:4
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作者 刘培文 陈宇婷 +1 位作者 顾金保 陈晓光 《南方医科大学学报》 CAS CSCD 北大核心 2013年第11期1583-1589,共7页
目的分离、鉴定和分析埃及伊蚊性别决定基因Transformer 2(Aaetra2)。方法通过生物信息学方法与分子生物学方法获得了Aaetra2基因的全长。通过与已知物种tra2的比较,分析Aaetra2的基因结构特点与分子进化特征,通过RT-PCR方法验证Aaetra... 目的分离、鉴定和分析埃及伊蚊性别决定基因Transformer 2(Aaetra2)。方法通过生物信息学方法与分子生物学方法获得了Aaetra2基因的全长。通过与已知物种tra2的比较,分析Aaetra2的基因结构特点与分子进化特征,通过RT-PCR方法验证Aaetra2的时间与组织表达特点。结果分离并鉴定Aaetra2-α与Aaetra2-β两个基因,它们位于染色体不同部位,通过选择性启动子的剪切策略进行自我调控,转录多种mRNA。埃及伊蚊TRA2蛋白具有保守的RRM、RS1、RS2和linker功能结构域区。Aaetra2表达方式无时间特异性的,从卵持续性表达至成虫阶段,且无性别特异性表达与组织特异性表达。结论 Aaetra2具有保守的昆虫性别决定基因tra2的功能结构域与表达特征,对其深入研究将为其最终应结合释放携带显性致死基因的昆虫技术应用于蚊虫的防制提供理论依据。 展开更多
关键词 埃及伊蚊 transformer2 性别决定基因 显性致死基因
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运行工况对超临界CO_(2)干气密封端面热力学过程及稳态性能影响研究 被引量:1
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作者 江锦波 陈竹鑫 +5 位作者 肖洋溢 彭新 陈源 于辰 孟祥铠 彭旭东 《化工学报》 北大核心 2025年第6期2913-2928,共16页
超临界CO_(2)压缩机干气密封因密封介质在临界点工况附近的物性特殊性和高参数化,密封间隙内介质流动呈现出多相流动、高度湍流化和物性畸变特征。以微段组合型槽干气密封为研究对象构建了轴向力平衡条件下考虑实际流体效应的超临界CO_... 超临界CO_(2)压缩机干气密封因密封介质在临界点工况附近的物性特殊性和高参数化,密封间隙内介质流动呈现出多相流动、高度湍流化和物性畸变特征。以微段组合型槽干气密封为研究对象构建了轴向力平衡条件下考虑实际流体效应的超临界CO_(2)干气密封热动力润滑相变仿真模型,提出了密封端面热力学过程表征方法,研究了转速、进气压力和进气温度等运行工况参数对超临界CO_(2)干气密封端面热力学过程、流场参数和稳态性能的影响。结果表明:进气温度的提高对于抑制密封端面液相凝析效果显著;转速和进气压力的增大只能抑制槽区液相凝析,增大端面非液相区面积,但对密封坝气液混相区影响不大,当进气温度达到320 K和340 K时,端面纯液相区和气液混相区先后消失;提高非液相区面积,对于增大密封气膜刚度是有利的。 展开更多
关键词 超临界CO_(2) 干气密封 相变 工况参数 热力学过程
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基于DCNv2和Transformer Decoder的隧道衬砌裂缝高效检测模型研究 被引量:4
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作者 孙己龙 刘勇 +4 位作者 周黎伟 路鑫 侯小龙 王亚琼 王志丰 《图学学报》 CSCD 北大核心 2024年第5期1050-1061,共12页
为解决因衬砌裂缝性状随机、分布密集、标注框分辨率低所导致的现有模型识别精度低、检测速度慢及参数量庞大等问题,以第2版可变形卷积网络(DCNv2)和端到端变换器解码器(Transformer Decoder)为基础对YOLOv8网络框架进行改进,提出了面... 为解决因衬砌裂缝性状随机、分布密集、标注框分辨率低所导致的现有模型识别精度低、检测速度慢及参数量庞大等问题,以第2版可变形卷积网络(DCNv2)和端到端变换器解码器(Transformer Decoder)为基础对YOLOv8网络框架进行改进,提出了面向衬砌裂缝的检测模型DTD-YOLOv8。首先,通过引入DCNv2对YOLOv8主干卷积网络C2f进行融合以实现模型对裂缝形变特征的准确快速感知,同时采用Transformer Decoder对YOLOv8检测头进行替换以实现端到端框架内完整目标检测流程,从而消除因Anchor-free处理模式所带来的计算消耗。采用自建裂缝数据集对SSD,Faster-RCNN,RT-DETR,YOLOv3,YOLOv5,YOLOv8和DTD-YOLOv8的7种检测模型进行对比验证。结果表明:改进模型F1分数和mAP@50值分别为87.05%和89.58%;其中F1分数相较其他6种模型分别提高了14.16%,7.68%,1.55%,41.36%,8.20%和7.40%;mAP@50分别提高了28.84%,15.47%,1.33%,47.65%,10.14%和10.84%。改进模型参数量仅为RT-DETR的三分之一,检测单张图片的速度为16.01 ms,FPS为65.46帧每秒,对比其他模型检测速度得到提升。该模型在面向运营隧道裂缝检测任务需求时能够表现出高效的性能。 展开更多
关键词 隧道工程 目标检测 2版可变形卷积网络 transformer Decoder 衬砌裂缝
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基于CNN和Transformer双流融合的人体姿态估计
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作者 李鑫 张丹 +2 位作者 郭新 汪松 陈恩庆 《计算机工程与应用》 北大核心 2025年第5期187-199,共13页
卷积神经网络(CNN)和Transformer模型在人体姿态估计中有着广泛应用,然而Transformer更注重捕获图像的全局特征,忽视了局部特征对于人体姿态细节的重要性,而CNN则缺乏Transformer的全局建模能力。为了充分利用CNN处理局部信息和Transfor... 卷积神经网络(CNN)和Transformer模型在人体姿态估计中有着广泛应用,然而Transformer更注重捕获图像的全局特征,忽视了局部特征对于人体姿态细节的重要性,而CNN则缺乏Transformer的全局建模能力。为了充分利用CNN处理局部信息和Transformer处理全局信息的优势,构建一种CNN-Transformer双流的并行网络架构来聚合丰富的特征信息。由于传统Transformer的输入需要将图片展平为多个patch,不利于提取对位置敏感的人体结构信息,因此将其多头注意力结构进行改进,使模型输入能够保持原始2D特征图的结构;同时提出特征耦合模块融合两个分支不同分辨率下的特征,最大限度地保留局部特征与全局特征;最后引入改进后的坐标注意力模块(coordinate attention),进一步提升网络的特征提取能力。在COCO和MPII数据集上的实验结果表明所提模型相对目前主流模型具有更高的检测精度,从而说明所提模型能够充分捕获并融合人体姿态中的局部和全局特征。 展开更多
关键词 卷积神经网络 transformER 局部特征 全局特征 2D特征图 特征耦合
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青虾transformer-2基因RNA干扰规律的研究 被引量:5
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作者 江丰伟 傅洪拓 +6 位作者 乔慧 张文宜 蒋速飞 熊贻伟 孙盛明 龚永生 金舒博 《中国农学通报》 CSCD 2014年第32期32-37,共6页
通过对青虾性别调控相关基因transformer-2(tra-2)的RNA干扰规律进行研究,探讨了tra-2基因RNA干扰的最适注射部位、注射剂量、干扰效果以及干扰规律等。通过对青虾肌肉、心脏、围心腔和眼柄基部注射比较发现,围心腔注射死亡率最低,适宜... 通过对青虾性别调控相关基因transformer-2(tra-2)的RNA干扰规律进行研究,探讨了tra-2基因RNA干扰的最适注射部位、注射剂量、干扰效果以及干扰规律等。通过对青虾肌肉、心脏、围心腔和眼柄基部注射比较发现,围心腔注射死亡率最低,适宜RNA干扰研究。采用4μg/g的dsRNA剂量进行时间依赖性干扰试验,RT-PCR检验注射后第1,7,14天的卵巢tra-2表达量,结果显示第7天基因表达量出现显著降低(P<0.05)。不同剂量水平(0.4μg/g、4μg/g以及12μg/g)干扰研究发现,0.4μg/g dsRNA没有干扰结果,4μg/g和12μg/g剂量的干扰效果均显著。与4μg/g的剂量相比,12μg/g的dsRNA能在较短时间内起到明显的干扰效果,且能持续较长的时间,表明干扰规律会随着剂量的改变而变化。但两组tra-2的最低表达量分别为正常水平的23%和21%,无显著差异(P>0.05)。 展开更多
关键词 青虾 RNAI transformer-2 注射剂量 注射部位 干扰规律
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火针联合董氏奇穴针刺治疗肩袖损伤的疗效观察及对关节功能及血清PGE_(2)和TGF-β1的影响 被引量:1
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作者 何天峰 邴兴红 +9 位作者 郭彧赟 段希栋 周丽艳 丁金磊 马洁 王茜 李英 安军伟 陶善平 卜利锋 《上海针灸杂志》 2025年第1期99-104,共6页
目的观察火针联合董氏奇穴针刺治疗肩袖损伤的临床疗效及对关节功能及血清前列腺素E_(2)(prostaglandin E_(2),PGE_(2))和转化生长因子-β1(transforming growth factor-β1,TGF-β1)的影响。方法将100例肩袖损伤患者随机分为对照组(50... 目的观察火针联合董氏奇穴针刺治疗肩袖损伤的临床疗效及对关节功能及血清前列腺素E_(2)(prostaglandin E_(2),PGE_(2))和转化生长因子-β1(transforming growth factor-β1,TGF-β1)的影响。方法将100例肩袖损伤患者随机分为对照组(50例)和观察组(50例)。对照组予以电针联合董氏奇穴针刺治疗,观察组予以火针联合董氏奇穴针刺治疗。检测视觉模拟量表(visual analog scale,VAS)和美国加利福尼亚大学洛杉矶分校(University of California,Los Angeles,UCLA)肩关节评分、肩关节活动度(range of motion,ROM)及血清PGE_(2)和TGF-β1水平。结果观察组总有效率高于对照组(P<0.05)。治疗后及4周随访时,两组VAS评分及血清PGE_(2)和TGF-β1水平均低于治疗前(P<0.05),且观察组均低于对照组(P<0.05);两组UCLA肩关节评分和肩关节ROM均高于治疗前(P<0.05),且观察组均高于对照组(P<0.05)。4周随访时,两组VAS评分、UCLA肩关节评分、肩关节ROM及血清PGE_(2)和TGF-β1水平与治疗后比较差异无统计系意义(P>0.05)。治疗后血清PGE_(2)、TGF-β1水平与VAS评分呈正相关,与UCLA肩关节评分呈负相关。结论火针和电针联合董氏奇穴针刺治疗肩袖损伤均可缓解疼痛、改善肩关节功能,但火针优于电针,其机制可能与降低血清PGE_(2)和TGF-β1水平有关。 展开更多
关键词 针刺疗法 火针疗法 董氏奇穴 电针 肩袖损伤 疼痛 关节功能 前列腺素E_(2) 转化生长因子-β1
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Hp阳性早期胃癌患者肿瘤组织中TGF-β_(1)mRNA、MMP-2 mRNA、PBP1A mRNA的表达水平及其与复发的关系 被引量:1
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作者 沙金平 徐赟 +1 位作者 蒋冬 薛萌 《海南医学》 2025年第7期996-1001,共6页
目的探讨幽门螺杆菌(Hp)阳性早期胃癌患者肿瘤组织中转化生长因子-β_(1)(TGF-β_(1))mRNA、金属基质蛋白酶-2(MMP-2)mRNA、青霉素结合蛋白1A(PBP1A)m RNA表达水平与复发的关系,并分析其对复发的预测价值。方法选取2018年3月至2023年7... 目的探讨幽门螺杆菌(Hp)阳性早期胃癌患者肿瘤组织中转化生长因子-β_(1)(TGF-β_(1))mRNA、金属基质蛋白酶-2(MMP-2)mRNA、青霉素结合蛋白1A(PBP1A)m RNA表达水平与复发的关系,并分析其对复发的预测价值。方法选取2018年3月至2023年7月南阳市中心医院收治的214例Hp阳性早期胃癌患者进行前瞻性研究,所有患者均行内镜黏膜下剥离术(ESD),采用实时荧光定量聚合酶链反应(qRT-PCR)法检测肿瘤组织、癌旁组织中TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平,并分析其与临床病理特征相关性。依据ESD术后是否复发分为复发组、未复发组,采用q RT-PCR法检测两组患者的TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平。采用偏相关性分析肿瘤组织中TGF-β_(1)m RNA、MMP-2 m RNA、PBP1A m RNA表达水平与复发的关系。采用受试者工作特征(ROC)曲线分析TGF-β_(1)m RNA、MMP-2 mRNA、PBP1A m RNA表达水平对复发的预测价值。结果肿瘤组织中TGF-β_(1)mRNA、MMP-2 m RNA表达水平分别为1.04±0.26、1.45±0.31,明显高于癌旁组织的0.85±0.14、1.18±0.25,PBP1A m RNA表达水平为0.31±0.10,明显低于癌旁组织的0.43±0.12,差异均有统计学意义(P<0.05);列联相关系数C分析显示,肿瘤组织中TGF-β_(1)mRNA、MMP-2 m RNA表达水平与临床分期、浸润深度、淋巴结转移呈正相关(P<0.05),与分化程度呈负相关(P<0.05),而PBP1A m RNA表达水平与临床分期、浸润深度、淋巴结转移呈负相关(P<0.05),与分化程度呈正相关(P<0.05);复发组患者的TGF-β_(1)mRNA、MMP-2 m RNA表达水平分别为1.31±0.25、1.74±0.31,明显高于未复发组的1.01±0.20、1.42±0.25,PBP1A mRNA表达水平为0.18±0.05,明显低于未复发组的0.32±0.10,差异均有统计学意义(P<0.05);偏相关性分析显示,肿瘤组织中TGF-β_(1)mRNA、MMP-2m RNA、PBP1A m RNA表达水平与复发显著相关(P<0.05);TGF-β_(1)mRNA、MMP-2 mRNA、PBP1A mRNA单项及联合预测复发的曲线下面积(AUC)分别为0.755、0.742、0.795、0.915,敏感度为75.00%、70.00%、75.00%、80.00%,特异度为72.25%、67.54%、76.95%、95.81%,且预测效能显著高于各指标单独预测价值(Z=2.376、2.413、1.997,P=0.018、0.016、0.046)。结论Hp阳性早期胃癌患者肿瘤组织中TGF-β_(1)m RNA、MMP-2 m RNA表达水平升高,PBP1A m RNA表达水平降低,且与临床病理特征、复发密切相关,联合检测其水平对复发具有较高的预测价值。 展开更多
关键词 胃癌 幽门螺杆菌 转化生长因子-β_(1) 金属基质蛋白酶-2 青霉素结合蛋白1A 复发 预测
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