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Comparison of Starch Granule Size Distribution Between Hard and Soft Wheat Cultivars in Eastern China 被引量:9
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作者 LI Wen-yang YAN Su-hui YIN Yah-ping LIYong LIANG Tai-bo GU Feng DAI Zhong-min WANG Zhen-lin 《Agricultural Sciences in China》 CAS CSCD 2008年第8期907-914,共8页
Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and functionality. Two types of wheat cultivars, the hard and soft wheat cultivars, grown at Tai'an Ex... Granule size distribution of wheat starch is an important characteristic that can affect its chemical composition and functionality. Two types of wheat cultivars, the hard and soft wheat cultivars, grown at Tai'an Experimental Station of Shandong Agricultural University, Taian, Shandong, China, were examined in this study. The granule size distribution and amylose contents in wheat grains were studied and compared, and relationships between the properties were identified. A clear bimodal distribution of granule size was shown in all wheat cultivars. Volume distribution of starch granules shows the typical bimodal with peak values in the ranges of 5.6-6.1μm and 20.7-24.9μm, respectively. Also, granule surface area distribution was bimodal with peak values in the ranges of 2.4-3.2μm and 20.7-24.9μm, respectively. Number distribution of granules was a typical population with a peak value in the range of 0.54-1.05μm. Contributions from the granules 〈 2.8μm and 〈 9.9μm to the total volume were in the ranges of 94.2-95.1% and 99.7-99.9% of total number, respectively. Proportions of granules〈2.8μm, 2.8-9.9μm, 9.9-22.8μm, and 22.8-42.8μm were in the ranges of 12.9-14.3%, 28.4-31.1%, 33.5-35.6%, and 19.7-22.7% for hard wheat, and 10.3-13.9%, 26.6-28.1%, 32.7-34.6%, and 24.2-27% for soft wheat. Hard wheat had greater B-type granules ( 〈 9.9μm), and had fewer granules of 22.8-42.8μm than soft wheat. Amylose content was positively related to volume percentage of granules 22.8-42.8μm, and negatively related to volume percentage of granules 2.8-22.8μm. 展开更多
关键词 wheat (Triticum aestivum L.) starch granule size distribution AMYLOSE hard wheat soft wheat
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Magnetic Properties Hard-Soft SmCo<sub>5</sub>-FeNi and SmCo<sub>5</sub>-FeCo Composites Prepared by Electroless Coating Technique 被引量:3
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作者 M. Lamichanne B. K. Rai +2 位作者 S. R. Mishra V. V. Nguyen J. P. Liu 《Open Journal of Composite Materials》 2012年第4期119-124,共6页
Composites of SmCo5-FeNi and SmCo5-FeCo, hard-soft magnetic materials, have been synthesized via electroless plating of magnetically hard SmCo5 powder particles with magnetically soft FeNi and FeCo, respectively. The ... Composites of SmCo5-FeNi and SmCo5-FeCo, hard-soft magnetic materials, have been synthesized via electroless plating of magnetically hard SmCo5 powder particles with magnetically soft FeNi and FeCo, respectively. The influence of coating thickness of soft magnetic layers on the structure and magnetic properties of the composite has been studied. Overall FeNi coating was found to be less dense compared to FeCo for the same plating duration. Structurally the coat ing was found to be nodular in morphology. These coating have dramatic effect on the overall magnetic property of the composite. As compared to FeNi coated SmCo5 composite, two-fold increase in the saturation magnetization has been observed upon coating SmCo5 (Ms^28 emu/g) with FeCo to a value 56 emu/g. The coercivity of composite powder was found to decrease with increasing the coating layer thickness. The absence of exchange spring behavior in the hard-soft composite is attributed to magnetically soft layer thickness exceeding the theoretical length limit for exchange-spring coupling. 展开更多
关键词 ELECTROLESS Plating hard-soft COMPOSITES Exchange Spring
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Constitutive model for methane desorption and diffusion based on pore structure differences between soft and hard coal 被引量:9
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作者 Liu Yanwei Wang Dandan +2 位作者 Hao Fuchang Liu Mingju Mitri Hani S. 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第6期937-944,共8页
This paper aims to improve the accuracy and applicability of gas diffusion mathematical models from coal particles. Firstly, a new constitutive model for gas diffusion from coal particles with tri-disperse pore struct... This paper aims to improve the accuracy and applicability of gas diffusion mathematical models from coal particles. Firstly, a new constitutive model for gas diffusion from coal particles with tri-disperse pore structure is constructed by considering the difference in characteristics between soft coal and hard coal.The analytical solution is then derived, that is, the quantitative relationship between gas diffusion rate(Qt/Q_∞) and diffusion time(t), The pore structure parameters of soft coal and hard coal from Juji coal mine are determined. Gas diffusion rules are numerically calculated and investigated by physical simulation methods. Lastly, the applicability of this model is verified. The results show that the homogeneous model only applies to the gas diffusion process of hard coal during the initial 10 min. The calculation results from this model and the physical experimental results of soft coal and hard coal are nearly identical during the initial 30 min. 展开更多
关键词 soft and hard coal Gas diffusion PORE structure CONSTITUTIVE models Physical simulation
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Influence of confining stress on fracture characteristics and cutting efficiency of TBM cutters conducted on soft and hard rock 被引量:2
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作者 刘京铄 曹平 +1 位作者 刘杰 蒋喆 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1947-1955,共9页
Combined with numerical simulation, the influence of confining stress on cutting process, fracture conditions and cutting efficiencies of soft and hard rock has been conducted on the triaxial testing machine(TRW-3000)... Combined with numerical simulation, the influence of confining stress on cutting process, fracture conditions and cutting efficiencies of soft and hard rock has been conducted on the triaxial testing machine(TRW-3000) designed and manufactured in Central South University(China). Results are obtained by performing analysis on the fracture scopes of cement and granite plates,the characteristics of cutting force in cutting processes and the cutting efficiency. Firstly, the increase of latitude fracture scope and the decrease of longitude fracture scope are both more notable in the tests conducted on cement plates subjected to the increasing confining stresses; secondly, the increase tendency of peak penetration forces obtained from tests conducted on granite plates is more obvious, however, the increase tendencies of average penetration forces achieved from cement and granite plates are close to each other; thirdly, the cutting efficiency could be improved by increasing the spacing between cutters when the confining stress which acts on soft and hard rock increases in a certain degree, and the cutting efficiency of soft rock is more sensitive to the varying confining stresses. 展开更多
关键词 triaxial testing machine numerical study tunnel boring machine(TBM) cutter confining stress soft and hard rock cutting efficiency
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Contrastive Study of Metadiscourse in the Conclusion of Academic Papers between Soft Science and Hard Science
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作者 徐伟伟 《海外英语》 2014年第3X期209-210,共2页
Academic paper as a genre is communicative.Interactional metadiscourse is one of the linguistic features that can significantly show the communicative feature of texts.With different research methodologies and charact... Academic paper as a genre is communicative.Interactional metadiscourse is one of the linguistic features that can significantly show the communicative feature of texts.With different research methodologies and characteristics,academic papers of hard and soft science present different degree of communicative features.The corpus of this study consists of 16 academic papers among which 8 are from hard science and 8 from soft science.This article aims to explore the different ways of scholars from soft and hard science to use metadiscourse in the conclusion part of their academic papers to exert lights to the pedagogical development of academic papers. 展开更多
关键词 academic papers BETWEEN soft SCIENCE and hard scie
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Proximal Femoral Cortical Thickness and Medullary Canal Diameter in Soft and Hard Water Regions
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作者 Ahmed Elmorsy Sarah Whitehouse +1 位作者 John Timperley Stephen Veitch 《Open Journal of Orthopedics》 2016年第3期58-62,共5页
This study compared proximal femoral morphology in patients living in soft and hard water regions. The proximal femoral morphology of two groups of 70 patients living in hard and soft water regions with a mean age of ... This study compared proximal femoral morphology in patients living in soft and hard water regions. The proximal femoral morphology of two groups of 70 patients living in hard and soft water regions with a mean age of 72.29 (range: 50 to 87 years) was measured using an antero-posterior radiograph of the non-operated hip with magnification adjusted. The medullary canal diameter at the level of the lesser trochanter (LT) was significantly wider in patients living in the hard water region (mean width: 1.9 mm wider;p = 0.003). No statistical significant difference was found in the medullary canal width at 10 cm below the level of LT, Dorr index, or Canal Bone Ratio (CBR). In conclusion, the proximal femoral morphology does differ in patients living in soft and hard water areas. These results may have an important clinical bearing in patients undergoing total hip replacement surgery. Further research is needed to determine whether implant survivorship is affected in patients living in hard and soft water regions. 展开更多
关键词 Hip hard Water soft Water Femoral Cortical Thickening Medullary Diameter
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XPS STUDIES OF IRRADIATED HARD AND SOFT Si—SiO_2
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作者 刘昶时 赵元富 +3 位作者 王忠燕 陈萦 刘芬 赵汝权 《Nuclear Science and Techniques》 SCIE CAS CSCD 1993年第3期181-185,共5页
The interracial structure of hard and soft oxides grown by dry oxidation on<100> n-type silicon substrates is examined using high resolution mild X-ray photoelectron spectroscopy (XPS) before and after irradiati... The interracial structure of hard and soft oxides grown by dry oxidation on<100> n-type silicon substrates is examined using high resolution mild X-ray photoelectron spectroscopy (XPS) before and after irradiation. Substantial differences in silicon of silica state (B.E. 103.4 eV), silicon of transitional state (B.E. 101.5 eV), surplus oxygen (B.E. 529.6 eV) and negative two-valence oxygen (B.E. 531.4 eV) are observed between the two kinds of samples. The XPS spectra strongly depend on the conditions of irradiation for soft samples, but do not as remarkablely as soft samples for hard samples. The effects of irradiation doses on XPS are greater than that of irradiation bias fields. Some viewpoints of irradiation induced hole electron pair are proposed to explain the results. 展开更多
关键词 XPS Radiation hard Radiation soft Si-SiO_2 Bias field Radiation dose
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Proteomic analysis reveals the differential proteins of endosperm between soft and hard wheat varieties
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作者 Feng Jia Haicheng Yin +2 位作者 Qi Wang Yu Chen Jinshui Wang 《Grain & Oil Science and Technology》 2019年第2期27-32,共6页
In this study,we revealed the differential proteins from the wheat endosperms using proteomic analysis and investigated their surface properties.The pattern of the polypeptides obtained from the Yangmai-15 and Yangmai... In this study,we revealed the differential proteins from the wheat endosperms using proteomic analysis and investigated their surface properties.The pattern of the polypeptides obtained from the Yangmai-15 and Yangmai-16 wheat varieties were compared using two-dimensional polyacrylamide gels.In addition,we compared the characteristics of the grain such as grain hardness,protein content,wet gluten,dough development time,dough stability,gliadin and glutenin contents between Yangmai-15 and Yangmai-16,and the results were significantly different.Notably,216 and 197 protein spots were separated from Yangmai-15 and Yangmai-16,respectively.The isoelectric points of the identified proteins ranged from 4 to 10 and the molecular weights of proteins varied from 10 to 100 kDa.Further,21 and 8 specific differential protein spots were identified fromthe flour of Yangmai-15 and Yangmai-16,respectively.The surface properties of identified peptides consisted of hydrophobic or hydrophilic residues,as well as randomly scattered residues.The proteomic analysis of the wheat endosperms provides a novel insight into the biochemical basis for the differences in physicochemical properties between the soft and hard wheat varieties. 展开更多
关键词 soft and hard wheat PROTEOME PEPTIDES surfaces ENDOSPERM proteins
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High energy product of isotropic bulk Sm-Co/α-Fe(Co)nanocomposite magnet with multiple hard phases and nanoscale grains 被引量:6
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作者 Shuo Li Longfei Ma +5 位作者 Jinkui Fan Jianping Yang Qiang Zheng Baoru Bian Jian Zhang Juan Du 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2021年第29期183-188,共6页
Nanocomposite magnets consisting of hard and soft magnetic phases have potential applications to be the next generation of permanent magnets with very high energy product and less expensive rare-earth elements.But it ... Nanocomposite magnets consisting of hard and soft magnetic phases have potential applications to be the next generation of permanent magnets with very high energy product and less expensive rare-earth elements.But it is still a big challenge to obtain bulk magnets with ideal microstructure and high performance.In this work,two-step warm processing at relative low temperatures had been adopted to obtain nearly theoretical density bulk nanocomposite magnets from amorphous/nanocrystalline powder precursors.Novel nanostructures consisting of multiple Sm-Co hard phases(SmCo_(5)as main phase,SmCO_(3),SmCo_(7),Sm_(2)Co_(17)as minor phases)and 25 wt%α-Fe(Co)soft phase,nanoscale grain size below 20 nm for both the hard phase and soft phase,and the diffusion of Fe and Co compositions had been obtained in bulk isotropic magnets.Besides the ideal nanostructures,a high coercivity of 5.9 kOe,M_(r)/M_(s)value of 0.78 and a high square degree of demagnetization curve S=0.47 were obtained.All of these factors together brought a new record-high energy product(BH)_(max)of 23.6 MGOe.These results make an important step toward fabricating novel nanostructure with high performance. 展开更多
关键词 hard/soft phase nanocomposite Isotropic bulk Magnetic properties Grain size Phase constitution
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An experimental study on fractural features of concrete samples containing hard inclusion 被引量:2
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作者 许昭永 王彬 +2 位作者 赵晋明 胡毅力 梅世蓉 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第1期95-103,共9页
The final fractural forms and variation status of hard inclusion samples under biaxial compression have been primarily studied in this paper. The lateral fractural forms of samples are mainly compressive shear fractu... The final fractural forms and variation status of hard inclusion samples under biaxial compression have been primarily studied in this paper. The lateral fractural forms of samples are mainly compressive shear fracture, two kinds appear on surface: one is strike slip fault with reversed thrust, and another is thrust. Some hard inclusions rupture and some do not while hard contact serves between hard inclusions and sample; main fracture bypasses hard inclusion while soft contact serves. Finally, process of stress concentration, yield, softening until failure for hard inclusions have been analysed under a certain condition. 展开更多
关键词 hard inclusion fractural forms hard contact soft contact
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“三软”厚煤层开采覆岩多层位离层注浆减沉技术及应用 被引量:5
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作者 郭文兵 吴东涛 +3 位作者 郭明杰 胡玉杭 杨伟强 王比比 《煤炭科学技术》 北大核心 2025年第5期1-12,共12页
采动覆岩离层注浆中注浆层位精准识别及保护层厚度合理确定,对防治地表沉陷、保护地表建(构)筑物具有重要意义。为了实现覆岩多层位离层精准注浆减沉,基于组合梁理论改进了离层位置判别方法,确定了覆岩多层位离层注浆充填位置;通过弹性... 采动覆岩离层注浆中注浆层位精准识别及保护层厚度合理确定,对防治地表沉陷、保护地表建(构)筑物具有重要意义。为了实现覆岩多层位离层精准注浆减沉,基于组合梁理论改进了离层位置判别方法,确定了覆岩多层位离层注浆充填位置;通过弹性薄板理论,建立了覆岩离层注浆保护层采动岩体结构力学模型;构建了覆岩多层位离层注浆充填空间的等效模型,并根据注浆空间上位岩层和下位岩层破断规律,给出了充填空间的最小和最大总体积;采用概率积分法并结合地表实际监测结果,评价了“三软”厚煤层覆岩多层位离层注浆效果,并对郑州矿区裴沟煤矿22151工作面开展了实例分析。结果表明:钻孔窥视验证了多层位离层注浆位置的准确性,在距煤层152.6 m中粒砂岩底部和距煤层168.6 m处细粒砂岩下方之间成功实施覆岩多层位离层注浆;工作面在开采厚度为7.1 m时,保护层厚度为25.2 m能够实现覆岩离层注浆工作的安全实施;理论计算注浆量为9.5×10^(4)~14.7×10^(4)t,实际工程注浆量约为13.3×10^(4)t,注采比约为0.41;采用覆岩多层位离层注浆开采后,地表最大下沉量为649.8 mm,大部分民房处地表最大水平变形值处于Ⅰ级损害程度内;覆岩多层位离层注浆开采地表沉陷控制效果显著,减沉率约77.91%。 展开更多
关键词 “三软”厚煤层 软硬交互覆岩 覆岩离层 多层位注浆 保护层 沉陷控制
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黔西矿区软硬分层煤温度-压力耦合影响瓦斯解吸试验 被引量:1
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作者 黄良 李希建 +1 位作者 刘钰 陈守坤 《工矿自动化》 北大核心 2025年第1期156-162,170,共8页
煤层瓦斯解吸特性对矿井瓦斯涌出规律和煤层气开发有重要影响,煤层温度和压力变化对软硬分层煤瓦斯解吸有明显控制作用。贵州黔西矿区煤层大多属于高瓦斯近距离突出煤层群,软硬结合较多,且煤层透气性低。为进一步明确该地区煤层瓦斯解... 煤层瓦斯解吸特性对矿井瓦斯涌出规律和煤层气开发有重要影响,煤层温度和压力变化对软硬分层煤瓦斯解吸有明显控制作用。贵州黔西矿区煤层大多属于高瓦斯近距离突出煤层群,软硬结合较多,且煤层透气性低。为进一步明确该地区煤层瓦斯解吸特性,以贵州黔西典型矿区小屯煤矿和青龙煤矿软硬分层煤为研究对象,利用HCA型高压容量法吸附装置对软硬分层煤进行不同温度、压力下的瓦斯解吸特征试验研究,对比分析温度、压力耦合变化对软硬分层煤瓦斯解吸特征的影响。结果表明:同一煤样温度、压力越高,瓦斯解吸初速度越大,对于0~120 s内的初始瓦斯解吸,瓦斯压力不占主导作用;软分层煤初始瓦斯解吸速率大于硬分层煤,硬分层煤累计瓦斯解吸量大于软分层煤,硬分层煤累计瓦斯解吸量最快在540 s内超过软分层煤;煤体暴露后60 s内含煤瓦斯解吸量变化最剧烈,且软分层煤前60 s解吸量所占比例大于硬分层煤,解吸更“活跃”;瓦斯解吸速率随压力的增加而升高,解吸速率可划分为3个阶段,即0~60 s为“解吸爆炸期”,60~1500 s为“解吸跳跃期”,1500~7200 s为“解吸稳定期”;软分层煤中值解吸时间受温度、压力影响大于硬分层煤,软分层煤瓦斯解吸主要集中在煤炭暴露后1800 s内。 展开更多
关键词 构造煤 软硬分层 瓦斯解吸速率 瓦斯解吸量 温度-压力耦合影响
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中国区域国别学知识体系建构:意义、原则及类型
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作者 陈杰 邓婷 《青海民族研究》 北大核心 2025年第3期124-130,共7页
随着区域国别学学科建设走向落地,尽早对中国区域国别学自主知识体系完成破立并举的建构,已成为区域国别学学术共同体的重要目标与艰巨任务。中国区域国别学知识体系构建是加快构建中国特色哲学社会科学的政策要求,也是中国与外部世界... 随着区域国别学学科建设走向落地,尽早对中国区域国别学自主知识体系完成破立并举的建构,已成为区域国别学学术共同体的重要目标与艰巨任务。中国区域国别学知识体系构建是加快构建中国特色哲学社会科学的政策要求,也是中国与外部世界高质量互动的实践目标,更是区域国别学学科构建的内在要求;其构建要遵循自主性、完整性、实践性与平等性原则。从类型学角度,区域国别学知识体系可分为硬知识体系与软知识体系,其既有“史”“志”“论”“图”等传统载体,也有“库”这一数字化载体,而以国别通、区域通为名的“人”则是其中最独特、最为重要的载体。 展开更多
关键词 区域国别学 知识体系 硬知识与软知识 类型学
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软硬知识协同的交通工程专业课程体系构建 被引量:1
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作者 赵靖 王嘉文 +1 位作者 姚佼 郑佳媛 《物流科技》 2025年第3期175-177,181,共4页
在“新工科”背景下,针对交通工程专业系统性强的特点,形成工程与管理、理论与实践融合的复合型人才培养模式是一个发展方向。上海理工大学以系统科学和管理科学与工程两大优势学科为依托,在管理学院开展软硬知识协同的交通工程本科教... 在“新工科”背景下,针对交通工程专业系统性强的特点,形成工程与管理、理论与实践融合的复合型人才培养模式是一个发展方向。上海理工大学以系统科学和管理科学与工程两大优势学科为依托,在管理学院开展软硬知识协同的交通工程本科教育教学。研究结合管理学院发展特点,针对交通工程专业课程建设展开系统性改革,从机遇与挑战、应对策略、建设方案、建设成效四个方面展开。课程体系从保障学科基础、对接优势学科、培养软实力和培养硬实力四个维度,形成基础理论、交通管理与大数据、智能交通和道路工程四个课程板块。初步形成了契合新工科建设内涵和管理学院特色的交通工科课程体系。 展开更多
关键词 交通工程 课程体系 软硬知识协同 系统科学
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机器视觉注意力机制研究综述 被引量:1
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作者 冯小丹 云利军 +1 位作者 高海峰 孟凤菊 《云南民族大学学报(自然科学版)》 2025年第4期453-463,共11页
概述机器视觉注意力机制的研究背景、发展中的显著工作及原理,综述软注意力机制中空间注意力机制、通道注意力机制、混合注意力机制和硬注意力机制,讨论Transformer的模型,并在分析各类改进模型的思路及特点的同时重点梳理了近3年的研... 概述机器视觉注意力机制的研究背景、发展中的显著工作及原理,综述软注意力机制中空间注意力机制、通道注意力机制、混合注意力机制和硬注意力机制,讨论Transformer的模型,并在分析各类改进模型的思路及特点的同时重点梳理了近3年的研究动态,最后探讨了注意力机制的在超参数优化、胶囊网络、神经架构搜索、多模态方面的潜在研究方向的应用展望. 展开更多
关键词 深度学习 注意力机制 软注意力机制 硬注意力机制 空间注意力机制 通道注意力机制 混合注意力机制
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软硬不均地层盾构机姿态控制试验研究
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作者 黄大维 陈凯 +2 位作者 徐长节 卢文剑 曾小涛 《岩土工程学报》 北大核心 2025年第10期2173-2182,共10页
软硬不均地层是盾构施工过程中常遇到的不良地质之一,盾构机在掘进软硬不均地层时,刀盘受力不均易导致盾构机姿态发生变化,从而导致盾构隧道偏离设计轴线。为研究盾构机掘进软硬不均地层时,刀盘受力和盾构机姿态变化之间的关系,设计了1... 软硬不均地层是盾构施工过程中常遇到的不良地质之一,盾构机在掘进软硬不均地层时,刀盘受力不均易导致盾构机姿态发生变化,从而导致盾构隧道偏离设计轴线。为研究盾构机掘进软硬不均地层时,刀盘受力和盾构机姿态变化之间的关系,设计了1∶10的模型盾构开挖施工模型试验,对试验中软硬不均地层中盾构机受力状况进行了分析,并对试验施工过程中盾构机的姿态进行了监测和分析。试验结果分析得出:①盾构机在开挖软硬不均地层时,刀盘掘进硬土层时开挖面土体反力大于刀盘掘进软土层时开挖面土体反力,刀盘将受到额外的开挖面扭矩,从而导致盾构机刀盘扭矩增大;②盾构法施工上软下硬地层时,盾构机刀盘逆时针转动,刀盘右侧接触硬土面积分别大于、小于、等于左侧时,盾构机刀盘受到开挖面反力整体合力分别向左下、左上、左;盾构机刀盘顺时针转动时,受力方向相反;③盾构机在开挖软硬不均地层时,刀盘转向应频繁规律的改变,正反转交替掘进;④盾构机在地层中的姿态变化受本身固有姿态和盾构机受力的综合影响。 展开更多
关键词 软硬不均 盾构施工 模型试验 盾构机受荷 盾构机姿态
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压力分散型锚索在软硬交替围岩中承载性能研究
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作者 任青阳 孟欣 +1 位作者 李世春 李洋 《建筑结构》 北大核心 2025年第17期155-161,共7页
基于实际工程现场调查,开展了承载板位于硬岩区及软岩区两种工况下的压力分散型锚索拉拔物理模型试验,对比分析了锚索在软硬交替围岩中的承载性能。结果表明:注浆体剪应力在硬岩区的减小速率明显大于其在软岩区,并在软硬岩层交界面处出... 基于实际工程现场调查,开展了承载板位于硬岩区及软岩区两种工况下的压力分散型锚索拉拔物理模型试验,对比分析了锚索在软硬交替围岩中的承载性能。结果表明:注浆体剪应力在硬岩区的减小速率明显大于其在软岩区,并在软硬岩层交界面处出现剪应力突变;软硬交替围岩中,承载板的布设位置对压力分散型锚索的承载性能影响显著,承载板位于硬岩工况下的极限承载力、剪应力峰值分别为承载板位于软岩工况下的1.22倍及1.49倍,表明承载板设置于硬岩区时,锚索能获得较高的承载性能。 展开更多
关键词 压力分散型锚索 软硬交替围岩 承载性能 模型试验
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邻近营业线地基隔离桩防护效果离心模型试验研究
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作者 秦尚林 杨莹 +2 位作者 陈尚勇 毛鹏恺 李剑 《铁道建筑》 北大核心 2025年第10期133-140,共8页
为研究新建铁路路基与营业线铁路路基坡脚相接条件下,隔离桩桩长和桩间距对防护效果的影响,本文以上海地区深厚软土层某既有铁路工程为背景,进行了两组离心模型试验。结果表明:隔离桩桩长是影响既有线路路基附加沉降和隔离防护效果的关... 为研究新建铁路路基与营业线铁路路基坡脚相接条件下,隔离桩桩长和桩间距对防护效果的影响,本文以上海地区深厚软土层某既有铁路工程为背景,进行了两组离心模型试验。结果表明:隔离桩桩长是影响既有线路路基附加沉降和隔离防护效果的关键因素,桩长越长,水平位移沿深度方向的分布更趋于线性,对既有线路路基水平位移控制效果越明显,隔离防护作用越大;在上软下硬土层条件及特定桩基加固工况下,当隔离桩桩间距分别设置为1.2、2.5 m时,新线施工过程中隔离桩对邻近营业线地基的隔离效果无明显差异;新线加固桩的加固效果对隔离桩和既有线路路基的沉降和水平位移有显著影响,当加固桩桩底承载力充足时,桩顶附近水平位移相对较小,有助于减小对既有路基的影响。 展开更多
关键词 铁路路基 邻近营业线 隔离桩 离心模型试验 防护效果 上软下硬地层 位移
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人工智能国际法治理:现状、挑战和完善路径
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作者 张卫彬 朱若彤 《阜阳师范大学学报(社会科学版)》 2025年第5期112-120,共9页
人工智能技术的全球化发展推动国际法治理呈现“软法主导、硬法萌芽”的新格局。在以伦理准则、行业指引等软法机制为主的治理框架下,国际规范呈现高度多元化特征,但具备法律约束力的国际硬法仍处于滞后发展阶段,导致现有国际法在应对... 人工智能技术的全球化发展推动国际法治理呈现“软法主导、硬法萌芽”的新格局。在以伦理准则、行业指引等软法机制为主的治理框架下,国际规范呈现高度多元化特征,但具备法律约束力的国际硬法仍处于滞后发展阶段,导致现有国际法在应对主权博弈、规范构建和国际合作机制层面面临诸多挑战。为应对上述挑战,人工智能国际法治理亟须摆脱技术霸权困境、完善全球伦理治理框架和健全国际合作机制,为构建公平、安全、包容的全球人工智能治理秩序提供理论支撑及制度保障。 展开更多
关键词 人工智能 国际法治理 软法 硬法
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