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Structure-aware fusion network for 3D scene understanding
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作者 Haibin YAN Yating LV Venice Erin LIONG 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2022年第5期194-203,共10页
In this paper,we propose a Structure-Aware Fusion Network(SAFNet)for 3D scene understanding.As 2D images present more detailed information while 3D point clouds convey more geometric information,fusing the two complem... In this paper,we propose a Structure-Aware Fusion Network(SAFNet)for 3D scene understanding.As 2D images present more detailed information while 3D point clouds convey more geometric information,fusing the two complementary data can improve the discriminative ability of the model.Fusion is a very challenging task since 2D and 3D data are essentially different and show different formats.The existing methods first extract 2D multi-view image features and then aggregate them into sparse 3D point clouds and achieve superior performance.However,the existing methods ignore the structural relations between pixels and point clouds and directly fuse the two modals of data without adaptation.To address this,we propose a structural deep metric learning method on pixels and points to explore the relations and further utilize them to adaptively map the images and point clouds into a common canonical space for prediction.Extensive experiments on the widely used ScanNetV2 and S3DIS datasets verify the performance of the proposed SAFNet. 展开更多
关键词 3D point clouds Data fusion structure-aware 3D scene understanding Deep metric learning
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The collaborative cross mouse for studying the effect of host genetic background on memory impairments due to obesity and diabetes 被引量:1
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作者 Avia Paz Kareem Midlej +2 位作者 Osayd Zohud Iqbal MLone Fuad A.Iraqi 《Animal Models and Experimental Medicine》 2025年第1期126-141,共16页
Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D... Background:Over the past few decades,a threefold increase in obesity and type 2 diabetes(T2D)has placed a heavy burden on the health-care system and society.Previous studies have shown correlations between obesity,T2D,and neurodegenera-tive diseases,including dementia.It is imperative to further understand the relation-ship between obesity,T2D,and cognitive deficits.Methods:This investigation tested and evaluated the cognitive impact of obesity and T2D induced by high-fat diet(HFD)and the effect of the host genetic background on the severity of cognitive decline caused by obesity and T2D in collaborative cross(CC)mice.The CC mice are a genetically diverse panel derived from eight inbred strains.Results:Our findings demonstrated significant variations in the recorded phenotypes across different CC lines compared to the reference mouse line,C57BL/6J.CC037 line exhibited a substantial increase in body weight on HFD,whereas line CC005 ex-hibited differing responses based on sex.Glucose tolerance tests revealed significant variations,with some lines like CC005 showing a marked increase in area under the curve(AUC)values on HFD.Organ weights,including brain,spleen,liver,and kidney,varied significantly among the lines and sexes in response to HFD.Behavioral tests using the Morris water maze indicated that cognitive performance was differentially affected by diet and genetic background.Conclusions:Our study establishes a foundation for future quantitative trait loci map-ping using CC lines and identifying genes underlying the comorbidity of Alzheimer's disease(AD),caused by obesity and T2D.The genetic components may offer new tools for early prediction and prevention. 展开更多
关键词 collaborative cross mouse DIABETES host genetic background memory impairments OBESITY
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Construction and characteristic analysis of background error covariance coupled with land surface temperature 被引量:1
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作者 Qihang Yang Yaodeng Chen +4 位作者 Luyao Qin Yuanbing Wang Deming Meng Xusheng Yan Xinyao Qian 《Atmospheric and Oceanic Science Letters》 2025年第3期7-12,共6页
Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimila... Land surface temperature(LST)is the key variable in land-atmosphere interaction,having an important impact on weather and climate forecasting.However,achieving consistent analysis of LST and the atmosphere in assimilation is quite challenging.This is because there is limited knowledge about the cross-component background error covariance(BEC)between LST and atmospheric state variables.This study aims to clarify whether there is a relationship between the error of LST and atmospheric variables,and whether this relationship varies spatially and temporally.To this end,the BEC coupled with atmospheric variables and LST was constructed(LST-BEC),and its characteristics were analyzed based on the 2023 mei-yu season.The general characteristics of LST-BEC show that the LST is mainly correlated with the atmospheric temperature and the correlation decreases gradually with a rise in atmospheric height,and the error standard deviation of the LST is noticeably larger than that of the low-level atmospheric temperature.The spatiotemporal characteristics of LST-BEC on the heavy-rain day and light-rain day show that the error correlation and error standard deviation of LST and low-level atmospheric temperature and humidity are closely related to the weather background,and also have obvious diurnal variations.These results provide valuable information for strongly coupled land-atmosphere assimilation. 展开更多
关键词 background error covariance Land surface temperature Error correlation Error standard deviation Data assimilation
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High summer background O_(3)levels in the desert of northwest China 被引量:1
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作者 Xinbing Ren Fang Wang +8 位作者 Bayi Wu Shaoting Zhang Lei Zhang Xingjun Zhou Yuanzhe Ren Yongjing Ma Feng Hao Yongli Tian Jinyuan Xin 《Journal of Environmental Sciences》 2025年第5期516-528,共13页
Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentratio... Generally speaking,the precursors of ozone(O_(3)),nitrogen oxides and volatile organic compounds are very low in desert areas due to the lack of anthropogenic emissions and natural emissions,and thus O_(3)concentrations are relatively low.However,high summer background concentrations of about 100μg/m^(3)or 60 ppb were found in the Alxa Desert in the highland of northwest China based on continuous summer observations from 2019 to 2021,which was higher than the most of natural background areas or clean areas in world for summer O_(3)background concentrations.The high O_(3)background concentrations were related to surface features and altitude.Heavy-intensity anthropogenic activity areas in desert areas can cause increased O_(3)concentrations or pollution,but also generated O_(3)depleting substances such as nitrous oxide,which eventually reduced the regional O_(3)baseline values.Nitrogen dioxide(NO2)also had a dual effect on O_(3)generation,showing promotion at low concentrations and inhibition at high concentrations.In addition,sand-dust weather reduced O_(3)clearly,but O_(3)eventually stabilized around the background concentration values and did not vary with sand-dust particulate matter. 展开更多
关键词 Alxa Desert O_(3)background concentration Anthropogenic effect Sand-dust weather Northwest China
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Association of the glycemic background patterns and the diabetes management efficacy in poorly controlled type 2 diabetes
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作者 Ayşe N Erbakan Müzeyyen Arslan Bahadır +6 位作者 FatoşN Kaya Büşra Güleç MiraçVural Keskinler Ümmügülsüm AktemurÇelik Özge Faydalıel Banu Mesçi Aytekin Oğuz 《World Journal of Diabetes》 SCIE 2025年第1期74-90,共17页
BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of ... BACKGROUND Inadequate glycemic control in patients with type 2 diabetes(T2DM)is a major public health problem and a significant risk factor for the progression of diabetic complications.AIM To evaluate the effects of intensive and supportive glycemic management strategies over a 12-month period in individuals with T2DM with glycated hemoglobin(HbA1c)≥10%and varying backgrounds of glycemic control.METHODS This prospective observational study investigated glycemic control in patients with poorly controlled T2DM over 12 months.Participants were categorized into four groups based on prior glycemic history:Newly diagnosed,previously well controlled with recent worsening,previously off-target but now worsening,and HbA1c consistently above 10%.HbA1c levels were monitored quarterly,and patients received medical,educational,and dietary support as needed.The analysis focused on the success rates of good glycemic control and the associated factors within each group.RESULTS The study showed significant improvements in HbA1c levels in all participants.The most significant improvement was observed in individuals newly diagnosed with diabetes:65%achieved an HbA1c target of≤7%.The results varied between participants with different glycemic control histories,followed by decreasing success rates:39%in participants with previously good glycemic control,21%in participants whose glycemic control had deteriorated compared to before,and only 10%in participants with persistently poor control,with mean HbA1c levels of 6.3%,7.7%,8.2%,and 9.7%,respectively.After one year,65.2%of the“newly diagnosed patients”,39.3%in the“previously controlled group”,21.9%in the“previously off-target but now worsened'”group and 10%in the“poorly controlled from the start”group had achieved HbA1c levels of 7 and below.CONCLUSION In poorly controlled diabetes,the rate at which treatment goals are achieved is associated with the glycemic background characteristics,emphasizing the need for tailored strategies.Therefore,different and comprehensive treatment approaches are needed for patients with persistent uncontrolled diabetes. 展开更多
关键词 Type 2 diabetes mellitus Glycated hemoglobin Glycemic control Patient-centered care Diabetes management glycemic background
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Comparison of Simulated Backgrounds with In-orbit Observations for HXI Onboard ASO-S
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作者 Hao-Xiang Wang Zhe Zhang +4 位作者 Wei Liu Xian-Kai Jiang Deng-Yi Chen Yi-Ming Hu Yang Su 《Research in Astronomy and Astrophysics》 2025年第3期141-153,共13页
The Hard X-ray Imager(HXI)payload,a component of China’s Advanced Space-based Solar Observatory satellite,is designed to observe solar X-ray emissions in the 30-200 keV range,with the aim of investigating nonthermal ... The Hard X-ray Imager(HXI)payload,a component of China’s Advanced Space-based Solar Observatory satellite,is designed to observe solar X-ray emissions in the 30-200 keV range,with the aim of investigating nonthermal physical processes during solar flares.Before launch,Geant4 simulations were employed to assess the onorbit background of the HXI instrument,evaluating its performance and potential to achieve its scientific objectives.This study addresses issues identified in previous simulations and conducts further analyses to examine the distribution of background counts across the 99 detectors.The results demonstrate alignment between simulations and observations at low and medium geomagnetic latitudes;however,challenges persist at high geomagnetic latitudes due to limitations in the current albedo photon model.This investigation provides insights into background sources from various particles,enhances understanding of space background characteristics,and offers guidance for background subtraction in imaging processes. 展开更多
关键词 instrumentation detectors-Sun X-rays gamma-rays-(cosmology )cosmic background radiation-gamma-rays diffuse background
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Study on the Correction Method of Radiant Temperature Measurement of Turbine Blades Under the Background of High-Temperature Dynamics
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作者 Shengnan Liu Liwei Chen 《Instrumentation》 2025年第2期80-90,共11页
The turbine blades operate under high temperature and high pressure conditions,and when using radiation thermometry,the influence of radiation from surrounding blades leads to measurement errors.To address this issue,... The turbine blades operate under high temperature and high pressure conditions,and when using radiation thermometry,the influence of radiation from surrounding blades leads to measurement errors.To address this issue,this paper develops a three-dimensional discretized dynamic radiation transfer model based on the blade shape of the turbine.The relationship between the radiation angle coefficient of the surrounding blades and the rotation angle of the blade under test is analyzed.The radiation angle coefficient is calculated using the triangular element method,and temperature inversion is performed based on the effective emissivity to compute the measurement error.The results show that under dynamic high temperature conditions,the temperature measurement error caused by reflection at the selected 60%leaf height point varies with the rotation angle,and the maximum reaches 25.58K.The angular coefficient exhibits periodic fluctuations with changes in rotation angle,and the maximum effective emissivity increases as the rotation angle increases.As the blade height increases,the impact of reflected radiation on radiometric temperature measurement errors shows a decreasing trend.This study provides a reference for radiation thermometry in dynamic high-temperature environments. 展开更多
关键词 radiation temperature measurement dynamic background turbine blades effective emissivity ERROR
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Enhanced suppression of background in capture reaction measurements with LAMBDA-Ⅱin ground laboratories
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作者 Lu-Yang Song Lin Wang +22 位作者 Jun Su Li-Yong Zhang Jian-Jun He Shi-Lun Jin Fei Lu Yang-Ping Shen Jun-Feng Chen Yao-De Sheng Xin Chen Shen Lin Zhi-Wei Qin Zi-Ming Li Hao Zhang Luo-Huan Wang Yin-Ji Chen Xin-Zhi Jiang Zhi-Lin Shen Xin-Yue Li Feng-Cheng Liu Yi-Tong Huang Si-Ze Chen Bing Guo Wei-Ping Liu 《Nuclear Science and Techniques》 2025年第11期273-282,共10页
The precise determination of cross sections for key nuclear reactions within the Gamow window is crucial for advancing the study of stellar evolution and nucleosynthesis.However,extremely low reaction yields combined ... The precise determination of cross sections for key nuclear reactions within the Gamow window is crucial for advancing the study of stellar evolution and nucleosynthesis.However,extremely low reaction yields combined with the cosmic-ray-induced background make these measurements highly challenging,particularly for capture reactions.This work demonstrates the second configuration of the large-scale modular BGO detection array(LAMBDA-Ⅱ)designed to capture reaction measurements and introduces a method for suppressingγ-ray detection background in ground laboratories.By employing active and passive shielding,the background of LAMBDA-Ⅱwas significantly reduced by approximately two orders of magnitude,reaching 8.1×10^(-3)and 1.0×10^(-3)keV^(-1)h^(-1)in the 6-11 and 11-20 MeV energy ranges,respectively.When combined with a mA-scale intensity beam,this reduced background enables the investigation of several capture reactions of astrophysical interest in ground laboratories. 展开更多
关键词 Nuclear astrophysics Capture reaction background Summing technique γdetector array SHIELDING
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Identification of QTL-by-environment interaction by controlling polygenic background effect
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作者 Fuping Zhao Lixian Wang Shizhong Xu 《Journal of Genetics and Genomics》 2025年第7期915-926,共12页
The quantitative trait loci(QTL)-by-environment(Q × E) interaction effect is hard to detect because there are no effective ways to control the genomic background. In this study, we propose a linear mixed model th... The quantitative trait loci(QTL)-by-environment(Q × E) interaction effect is hard to detect because there are no effective ways to control the genomic background. In this study, we propose a linear mixed model that simultaneously analyzes data from multiple environments to detect Q × E interactions. This model incorporates two different kinship matrices derived from the genome-wide markers to control both main and interaction polygenic background effects. Simulation studies demonstrate that our approach is more powerful than the meta-analysis and inclusive composite interval mapping methods. We further analyze four agronomic traits of rice across four environments. A main effect QTL is identified for 1000-grain weight(KGW), while no QTL are found for tiller number. Additionally, a large QTL with a significant Q × E interaction is detected on chromosome 7 affecting grain number, yield, and KGW. This region harbors two important genes, PROG1 and Ghd7. Furthermore, we apply our mixed model to analyze lodging in barley across six environments. The six regions exhibiting Q × E interaction effects identified by our approach overlap with the SNPs previously identified using EM and MCMC-based Bayesian methods, further validating the robustness of our approach. Both simulation studies and empirical data analyses show that our method outperforms all other methods compared. 展开更多
关键词 Q×E interaction Main effect META-ANALYSIS Mixed model Polygenic background
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A Preliminary Study on the Background of the Formation of the Meng Yao Zheng Dian
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作者 Hongying Wu Bao Long 《Journal of Clinical and Nursing Research》 2025年第2期93-101,共9页
Meng Yao Zheng Dian is one of the three classics of Mongolian medicine.It was written by Zhanbra Dorje,who was a famous Mongolian physician.The book was not only related to the author's origin,education and learni... Meng Yao Zheng Dian is one of the three classics of Mongolian medicine.It was written by Zhanbra Dorje,who was a famous Mongolian physician.The book was not only related to the author's origin,education and learning experience,but also closely related to the social development,cultural exchanges between Mongolian and Tibetan,and people's demand for Mongolian medicine at that time.The book in four languages indicates the name of Mongolian medicinal herbs,Mongolian of China,Tibetan of China,Chinese,Manchu medicine academic and cultural exchanges played a positive role in promoting the cultural exchanges,is a vivid embodiment of the cultural exchanges between Chinese nationalities and exchanges and mingling. 展开更多
关键词 Zhanbra Dorje Meng Yao Zheng Dian background of the book
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Interactions of the Background State and Eddies in Shaping Aleutian Low Variations
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作者 Nan LIN Tuantuan ZHANG +3 位作者 Qiaoling REN Ho-Nam CHEUNG Chang-Hoi HO Song YANG 《Advances in Atmospheric Sciences》 2025年第8期1548-1565,共18页
The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert dist... The Aleutian Low(AL)is a dominant feature of the mean circulation in the North Pacific during the winter season.The background stationary wave,air-sea interaction,and transient eddies over the North Pacific exert distinct impacts on the interannual variations of the AL intensity and position.In this study,we adopt the quasi-geostrophic geopotential tendency equation to investigate the roles of various physical processes in the maintenance and interannual variations of this system.The results show that absolute vorticity advection plays the most important role in the formation and maintenance of AL intensity,while high-frequency transient eddies contribute most to the meridional and zonal shifts of the AL.The high-frequency transient eddy vorticity forcing affects the AL through the barotropic energy conversion process,and,in turn,the AL enhances the high-frequency transient eddies through the baroclinic energy conversion process,forming a positive feedback.The associated high-frequency eddy kinetic energy anomalies exhibit an eastward movement toward the east coast of North America in the years of an intensified AL,which explains why a strengthened AL is often accompanied by an eastward movement.Furthermore,the energy conversion terms of high-frequency transient eddies are mostly located over the extratropical eastern North Pacific,leading to asymmetric features in the zonal movement of the AL. 展开更多
关键词 Aleutian Low interannual variations interactions between eddies and the background flow
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Rogue waves on a periodic background in the reduced Maxwell–Bloch system
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作者 YiJie Zhao Zhaqilao Niqi Ao 《Communications in Theoretical Physics》 2025年第8期25-34,共10页
In this paper,the nonlinearization of the Lax pair and the Darboux transformation method are used to construct the rogue wave on the elliptic function background in the reduced Maxwell–Bloch system,which is described... In this paper,the nonlinearization of the Lax pair and the Darboux transformation method are used to construct the rogue wave on the elliptic function background in the reduced Maxwell–Bloch system,which is described by four component nonlinear evolution equations(NLEEs).On the background of the Jacobian elliptic function,we obtain the admissible eigenvalues and the corresponding non-periodic eigenfunctions of the model spectrum problem.Then,with the help of the one-fold Darboux transformation and two-fold Darboux transformation,rogue waves on a dn-periodic background and cn-periodic background are derived,respectively.Finally,the corresponding complex dynamical properties and evolutions of the four components are illustrated graphically by choosing suitable parameters. 展开更多
关键词 Jacobian elliptic function Darboux transformation reduced Maxwell–Bloch system rogue waves on a periodic background
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Gravitational Wave Background from Extreme-Mass-Ratio Inspirals
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作者 Haoyu Zhao Yuanhao Zhang +1 位作者 Xilong Fan Wenbiao Han 《Chinese Physics Letters》 2025年第5期239-247,共9页
The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary ta... The gravitational wave background(GWB) produced by extreme-mass-ratio inspirals(EMRIs) serves as a powerful tool for probing the astrophysical and dynamical processes in galactic centers. EMRI systems are a primary target for the space-based detector laser interferometer space antenna due to their long-lived signals and high signal-to-noise ratios. This study explores the statistical properties of the GWB from EMRI, focusing on the calculation methods for the GWB, the astrophysical distribution of EMRI sources, and the influence of key parameters, including the spin of supermassive black holes(SMBHs) and the masses of compact objects(COs). By analyzing these factors, we determine the distribution range of the characteristic strain of the GWB from EMRIs. We find that the final eccentricity distributions appear to have negligible effect on the intensity of the GWB due to rapid circularization before they become detectable and the spin of the SMBH enhances the gravitational wave characteristic strain by approximately 1% compared to cases without spin effects. The masses of COs can also significantly affect the characteristic strain of the GWB from EMRIs, with black hole as CO producing a gravitational wave signal intensity that is approximately one order of magnitude higher compared to cases where neutron star or white dwarf are the COs. 展开更多
关键词 probing astrophysical dynamical processes galactic centers astrophysical distribution extreme mass ratio inspirals laser interferometer space antenna gravitational wave background calculation methods characteristic strain Laser Interferometer Space Antenna
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滇东北梅树村期磷矿成矿作用研究进展
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作者 熊灿娟 杨瑞东 +6 位作者 高军波 陈吉艳 蒋元 李智 彭柔 高川黔 庞雨雨 《地质论评》 北大核心 2026年第1期253-268,共16页
磷矿作为重要的非金属矿产资源,广泛应用于农业、工业和环保等领域。滇东北地区位于扬子克拉通西南缘,是磷矿资源的集中分布区,其成矿作用的研究具有重要的学术价值和经济意义。本文在大量查阅相关文献资料的基础上,系统总结了滇东北寒... 磷矿作为重要的非金属矿产资源,广泛应用于农业、工业和环保等领域。滇东北地区位于扬子克拉通西南缘,是磷矿资源的集中分布区,其成矿作用的研究具有重要的学术价值和经济意义。本文在大量查阅相关文献资料的基础上,系统总结了滇东北寒武纪梅树村期磷矿床在成矿地质背景、物质来源及成矿机制方面的研究进展。研究普遍认为,滇东北磷矿床主要形成于浅海碳酸盐台地及台地凹陷盆地,但在不同矿床中,具体的沉积古地理位置和古环境特征表现出一定的差异性。关于成矿物质来源,主要有陆源物质、生物源磷、海水和深部热液等多种不同观点,而成矿机制主要包括生物成磷作用、海相热水沉积作用及上升洋流等。尽管已有大量研究对磷矿的成因进行了探讨,但仍有多种不同认识,成矿背景、物质来源及成矿机制等方面的争议依然存在,影响了区域成矿模式的构建。未来的研究应加强利用显微组构的原位分析,结合多种地球化学手段,深入探讨滇东北磷块岩的成因机制和古海洋环境,构建滇东北磷块岩的成矿模式;这不仅有助于磷矿资源的勘探与开发,也将对扬子克拉通成矿系统的研究发挥重要作用。 展开更多
关键词 滇东北 磷矿 成矿背景 物质来源 成矿机制
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基于背景结构感知的小样本知识图谱补全
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作者 张静 潘景豪 姜文超 《计算机科学》 北大核心 2026年第2期331-341,共11页
小样本知识图谱补全旨在通过少量参考数据预测知识图谱中长尾关系的未知事实。如何在数据稀疏条件下高效编码实体和关系特征并构建有效的三元组评分函数对补全效果影响显著。现有的小样本知识图谱补全模型忽略了实体上下文背景结构信息... 小样本知识图谱补全旨在通过少量参考数据预测知识图谱中长尾关系的未知事实。如何在数据稀疏条件下高效编码实体和关系特征并构建有效的三元组评分函数对补全效果影响显著。现有的小样本知识图谱补全模型忽略了实体上下文背景结构信息对实体编码和评分函数的影响,导致关系表示学习能力不足。针对上述问题,提出了一种基于背景结构感知的小样本知识图谱补全模型(BSA)。首先,设计了一种实体对上下文背景结构信息交互指标,通过衡量邻居实体在结构上的影响,指导模型将注意力集中在与中心实体结构更相似的邻居节点,以减少噪声邻居的不良影响。其次,在关系表示学习阶段,引入背景知识图谱中语义和结构相似的关系信息进一步增强目标关系的嵌入表示。最后,在评分函数中引入头尾实体对的上下文信息交互指标,提升模型对复杂关系的推理能力。实验结果表明,与当前主流方法相比,BSA模型在NELL-One数据集测试中,MRR,Hit@5和Hit@1评价指标分别提高了0.4个百分点,0.8个百分点和0.5个百分点。在Wiki-One数据集测试中,MRR,Hit@10和Hit@5指标分别提高了1.9个百分点,2.2个百分点和2.2个百分点,充分证明了BSA模型的有效性。 展开更多
关键词 小样本知识图谱补全 背景结构感知 表示学习 注意力机制
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一种抗行人干扰的车辆重识别算法
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作者 曹仰杰 蔡吉灏 +1 位作者 王沛祺 杨聪 《郑州大学学报(工学版)》 北大核心 2026年第2期35-40,共6页
车辆重识别是实现车辆跟踪的基础,然而,行人干扰会显著影响车辆特征的提取,进而降低车辆重识别的准确性和精度。针对这一问题,提出一种名为轨迹优化与背景抑制的车辆重识别算法TRaBS。首先,使用ResNeXt101-IBN-a网络对车辆图像进行特征... 车辆重识别是实现车辆跟踪的基础,然而,行人干扰会显著影响车辆特征的提取,进而降低车辆重识别的准确性和精度。针对这一问题,提出一种名为轨迹优化与背景抑制的车辆重识别算法TRaBS。首先,使用ResNeXt101-IBN-a网络对车辆图像进行特征提取,得到车辆初始特征,同时应用背景抑制算法对摄像头画面进行特征计算,生成经过背景抑制处理的车辆特征;其次,为了降低行人对特征提取的干扰,采用欧几里得距离和高斯核函数,将车辆图像特征替换为更加稳定的轨迹特征,通过这些技术,TRaBS算法有效解决了车辆重识别中的行人干扰问题;最后,为全面验证TRaBS算法在应对行人干扰方面的有效性以及在无干扰环境下的通用性,设计并进行了对比实验与消融实验。实验结果表明:融合轨迹优化与背景抑制算法的车辆重识别模型在基准数据集以及引入行人干扰的衍生数据集上均取得了显著的效果。在VeRi-776数据集上,平均精度均值mAP达到了83.6%,Rank-1准确率达到了97.6%,显著优于现有方法。 展开更多
关键词 车辆重识别 行人干扰 轨迹优化 背景抑制 特征提取
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基于任务导向的人工智能基础通识课混合式教学
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作者 边小勇 盛玉霞 +2 位作者 王强 朱子奇 张凯 《计算机教育》 2026年第2期242-248,共7页
针对传统人工智能基础通识课教学目前存在的问题,提出将人工智能“知识—模型—案例”贯通的创新人才培养路径,阐述如何开展AI对话式教学、案例教学、翻转课堂等多维度混合式教学,如何由低阶到高阶进行知识设计、模型案例设计和应用评价... 针对传统人工智能基础通识课教学目前存在的问题,提出将人工智能“知识—模型—案例”贯通的创新人才培养路径,阐述如何开展AI对话式教学、案例教学、翻转课堂等多维度混合式教学,如何由低阶到高阶进行知识设计、模型案例设计和应用评价,以更好地激发学生从导知识、导应用到懂原理、懂应用,最后介绍具体实践,说明教学实践取得的成效。 展开更多
关键词 大语言模型 人工智能 模型案例设计 人才培养
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基于反射式谐振腔的宽谱光源驱动的谐振式光学陀螺
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作者 王颖 杨柳 +3 位作者 靳婷 徐辰龙 廉天航 张勇刚 《中国惯性技术学报》 北大核心 2026年第2期180-187,共8页
为抑制反射式谐振腔背景光,提出了一种基于反射式光纤环形谐振腔的宽谱光源驱动的谐振式光纤陀螺方案。首先介绍了所提方案的工作原理,分析了不同调制参数对解调曲线斜率的影响,为选取调制参数提升检测系统信噪比提供了理论支撑;其次,... 为抑制反射式谐振腔背景光,提出了一种基于反射式光纤环形谐振腔的宽谱光源驱动的谐振式光纤陀螺方案。首先介绍了所提方案的工作原理,分析了不同调制参数对解调曲线斜率的影响,为选取调制参数提升检测系统信噪比提供了理论支撑;其次,通过数值仿真研究了不同调制参数下散粒噪声以及相对强度噪声对陀螺角度随机游走的影响,并和传统方案做了比较;最后,搭建了实验系统对所提方案进行验证,实验采用直径为10 cm、长度约为100 m的光纤环形谐振腔作为敏感单元,测试结果表明陀螺的角度随机游走达到0.0019(°)/√h,零偏不稳定性为0.009(°)/h。所提方案在降低敏感单元损耗的同时,利用光学相消方法实现了背景光的抑制。此外,陀螺工作在探测光功率较低的点,可以有效降低噪声的影响。 展开更多
关键词 谐振式光纤陀螺 反射式谐振腔 光学相消方法 宽带光源 背景光噪声
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Research on Background and Utilization of Germplasm Resources in Maize 被引量:3
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作者 杨培珠 钟国祥 +4 位作者 谢虹 陈少方 苏立生 刘惠娈 张旭 《Agricultural Science & Technology》 CAS 2011年第10期1464-1467,共4页
[Objective] The research aimed at introducing the background and utilization of germplasm resources in maize.[Method] The research progress on genetic background and utilization of maize germplasm resources was compre... [Objective] The research aimed at introducing the background and utilization of germplasm resources in maize.[Method] The research progress on genetic background and utilization of maize germplasm resources was comprehensively reviewed in this paper,including maize heterotic groups and heterotic patterns,their flexible application in breeding and the utilization of various types of original materials.[Result] The results show that germplasm resource is the premise and basis for maize breeding.In-depth understanding and a reasonable selection of germplasm resources can significantly improve the breeding efficiency and speed up the breeding process.At the same time,it is considered that the selection and construction of original materials in maize breeding can not be limited to the heterotic groups and heterotic patterns,but has to be used reasonablely according to different types of germplasm resources and individual breeding objective and idea as well.[Conclusion] This study had broadened the idea and provided inspiration for the maize breeding practice in China. 展开更多
关键词 MAIZE Germplasm resources Genetic background UTILIZATION
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Mitochondrial DNA D-loop Variation and Genetic Background of Brahman Cattle 被引量:1
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作者 亐开兴 吴桂生 +7 位作者 廖祥龙 金显栋 赵刚 杨国荣 袁希平 黄必志 文际坤 张亚平 《Zoological Research》 CAS CSCD 北大核心 2006年第6期615-620,共6页
The complete mitochondrial DNA D-loop sequences from 10 stud Brahman cattle were sequenced and analyzed. The results showed that the genetic diversity of Brahman cattle was rich ; the rate of nucleotide variation, hap... The complete mitochondrial DNA D-loop sequences from 10 stud Brahman cattle were sequenced and analyzed. The results showed that the genetic diversity of Brahman cattle was rich ; the rate of nucleotide variation, haplotype diversity and nucleotide diversity were 6.25%, 0.978± 0.054 and 0.014 30± 0.008 68, respectively. Nine haplotypes were defined and fell into two distinct lineages, suggesting that Brahman cattle have both Bos indicus (Zebu) and B. taurus genetic background. The taurine haplotypes were predominant at 90% and only Brah-6 belonged to the Asian zebu mthaplotype. This indicates that Brahman cattle was one of the zebu breeds and inherited the excellent characteristics of both the Asian zebu and European beef cattle, such as easy calf delivery, high quality beef, heat tolerance and resistance to various parasites. Breeders introduced Brahman cattle to improve the productivity and adaptability of native cattle. The Zebu has evidently frequently introgressed into the modem taurine breeds. As for modem zebu breeds, B. taurus also highly contributed to their formation, except for the Asian zebu. Furthermore our results also confirm the hypothesis that B. indicus has undergone a separate domestication event and originated from the Indian subcontinent. 展开更多
关键词 Brahman cattle mtDNA D-loop polymorphism genetic background
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