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Quantifying TiO_2 Abundance of Lunar Soils:Partial Least Squares and Stepwise Multiple Regression Analysis for Determining Causal Effect

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Journal of Earth Science 2011年第5期22卷 549-565页

作者： lin li Department of Earth Sciences Indiana University-Purdue University Indianapolis IN 46202 USA

Partial least squares （PLS） regression was applied to the Lunar Soft Characterization Consortium （LSCC） dataset for spectral estimation of TiO2. The LSCC dataset was split into a number of subsets including the low-Ti, high-Ti, total mare soils, total highland, Apollo 16, and Apollo 14 soils to investigate the effects of interfering minerals and nonlinearity on the PLS performance. The PLS weight loading vectors were analyzed through stepwise multiple regression analysis （SMRA） to identify mineral species driving and interfering the PLS performance. PLS exhibits high performance for estimating TiO2 for the LSCC low-Ti and high-Ti mare samples and both groups analyzed together. The results suggest that while the dominant TiO2-bearing minerals are few, additional PLS factors are required to compensate the effects on the important PLS factors of minerals that are not highly corrected to TiO2, to accommodate nonlinear relationships between reflectance and TiO2, and to correct inconsistent mineral-TiO2 correlations between the high-Ti and iow-Ti mare samples. Analysis of the LSCC highland soil samples indicates that the Apollo 16 soils are responsible for the large errors of TiO2 estimates when the soils are modeled with other subgroups. For the LSCC Apollo 16 samples, the dominant spectral effects of plagioclase over other dark minerals are primarily responsible for large errors of estimated TiO2. For the Apollo 14 soils, more accurate estimation for TiO2 is attributed to the posi- tive correlation between a major TiOe-bearing component and TiO2, explaining why the Apollo 14 soils follow the regression trend when analyzed with other soils groups.

关键词： lunar soils LSCC dataset TiO2 abundance partial least squares stepwise multiple regression.

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Segmentation of the Ventricle Membranes in Short-Axis Sequences by Optical Flow Base on DLSRE Model

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Chinese Journal of Electronics 2021年第3期30卷 460-470页

作者： li lin WU Hengfei li Junhua Department of Electronics and Information Engineering Bozhou University Key Laboratory of Jiangxi Province for Image Processing and Pattern Recognition Nanchang Hangkong University

Recent studies have pointed out that the boundary of the extracted ventricle membranes is unsmooth, and the segmentation of the cardiac papillary muscle and trabecular muscle do inconformity the clinical requirements. To address these issues, this paper proposes an automatic segment algorithm for continuously extracting ventricle membranes boundary, which adopts optical flow field information and sequential images information. The images are cropped by frame difference method, which according to the continuity of adjacent slices of cardiac MRI images. The roughly boundary of epicardium is extracted by the Double level set region evolution(DLSRE) model, which combines image global information, local information and edge information. The ventricle endocardium and epicardial contours are tracked according to the optical flow field information between image sequences. The segmentation results are optimized by Delaunay triangulation algorithm. The experimental results demonstrate that the proposed method can improve the accuracy of segmenting the ventricle endocardium and epicardium contours, and segment the contour of the smooth ventricle membrane edge that meets the clinical definition.

关键词： edge information image sequences automatic segment algorithm sequential images information clinical requirements medical image processing cardiology optical flow base extracted ventricle membranes roughly boundary local information ventricle endocardium trabecular muscle optical flow field information continuously extracting ventricle membranes boundary DLSRE model biomedical MRI smooth ventricle membrane edge image global information mesh generation muscle short-axis sequences cardiac MRI images image segmentation cardiac papillary muscle frame difference method region evolution model

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调和分数Ornstein-Uhlenbeck金融模型的参数估计

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河南师范大学学报（自然科学版） 2025年第1期53卷 75-81页

作者：王继霞王琳李浩然河南师范大学数学与信息科学学院河南新乡453007 湖南大学经济管理研究中心长沙410012

为了描述金融资产价格过程的长相依性和自相似性,首先构建由调和分数布朗运动驱动的分数Ornstein-Uhlenbeck(O-U)模型.由于调和分数布朗运动是分数布朗运动的推广,故所构建的模型具有更广泛的应用.然后基于离散观测样本,利用最小二乘方... 详细信息

为了描述金融资产价格过程的长相依性和自相似性,首先构建由调和分数布朗运动驱动的分数Ornstein-Uhlenbeck(O-U)模型.由于调和分数布朗运动是分数布朗运动的推广,故所构建的模型具有更广泛的应用.然后基于离散观测样本,利用最小二乘方法,得到模型漂移参数的估计量,并证明了估计量的相合性和渐近分布.最后,通过模拟展示了所得估计量的有限样本性质,模拟结果显示估计量的值拟合参数真值的效果较好.

关键词：最小二乘估计调和分数布朗运动 Ornstein-Uhlenbeck过程相合性渐近分布

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Asymptotic solutions for the asymmetric flow in a channel with porous retractable walls under a transverse magnetic field

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Applied Mathematics and Mechanics(English Edition) 2018年第8期39卷 1147-1164页

作者： Hongxia GUO Ping lin lin li Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science School of Mathematics and Physics University of Science and Technology Beijing Division of Mathematics University of Dundee School of Mathematics and Physics University of South China

The self-similarity solutions of the Navier-Stokes equations are constructed for an incompressible laminar flow through a uniformly porous channel with retractable walls under a transverse magnetic field. The flow is driven by the expanding or contracting walls with different permeability. The velocities of the asymmetric flow at the upper and lower walls are different in not only the magnitude but also the direction. The asymptotic solutions are well constructed with the method of boundary layer correction in two cases with large Reynolds numbers, i.e., both walls of the channel are with suction, and one of the walls is with injection while the other one is with suction. For small Reynolds number cases, the double perturbation method is used to construct the asymptotic solution. All the asymptotic results are finally verified by numerical results.

关键词： laminar flow asymmetric flow asymptotic solution porous and retractable channel magnetic field

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Realising high aspect ratio 10 nm feature size in laser materials processing in air at 800 nm wavelength in the far-field by creating a high purity longitudinal light field at focus

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light(Science & Applications) 2022年第12期11卷 3028-3043页

作者： Zhaoqing li Olivier Allegre lin li Department of Mechanical Aerospace and Civil EngineeringThe University of ManchesterManchester M139PLUK

In semiconductor and data storage device manufacturing,it is desirable to produce feature sizes less than 30 nm with a high depth-to-width aspect ratio on the target material rapidly at a low ***,optical diffraction limits the smallest focused laser beam diameter to around half of the laser wavelength(λ/2).The existing approach to achieving nanoscale fabrication is mainly based on costly extreme ultraviolet(EUV)technology operating within the diffraction *** this paper,a new method is shown to achieve materials processing resolution down to 10 nm(λ/80)at an infrared laser wavelength of around 800 nm in the far-field,in air,well beyond the optical diffraction limit.A highquality longitudinal field with a purity of 94.7% is generated to realise this *** experiments and theoretical modelling have been carried out to verify and understand the *** ablation craters induced on polished silicon,copper,and sapphire are compared for different types of light *** of 10-30 nm in diameter are produced on sapphire with a depth-to-width aspect ratio of over 16 and a zero taper with a single pulse at 100-120 nJ pulse *** high aspect ratio sub-50 nm holes produced with single pulse laser irradiation are rarely seen in laser processing,indicating a new material removal mechanism with the longitudinal *** working distance(lens to target)is around 170μm,thus the material processing is in the far *** nano-holes can also be produced by adjusting the lens to the target distance.

关键词： sapphire field purity

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深度学习驱动下的目标检测研究进展综述

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计算机工程与应用 2025年第1期61卷 24-41页

作者：山显英张琳李泽慧北京建筑大学电气与信息工程学院北京102616

近年来,深度学习在GPU高性能计算能力的加持下得到了迅速推广,并在安防、医疗、工业等领域实现了广泛应用。目标检测模型的性能也在稳步提高,从传统的目标检测方法逐渐过渡到基于卷积神经网络(CNN)深度学习的进一步应用,极大地节省了人... 详细信息

近年来,深度学习在GPU高性能计算能力的加持下得到了迅速推广,并在安防、医疗、工业等领域实现了广泛应用。目标检测模型的性能也在稳步提高,从传统的目标检测方法逐渐过渡到基于卷积神经网络(CNN)深度学习的进一步应用,极大地节省了人力物力。通过参考大量文献,按照两阶段脉络梳理了目标检测的发展历程以及近年深度学习在目标检测领域内的研究进展,对比了在不同数据集上模型网络的性能,总结不同方法的优势与不足,并对领域内重要数据集作了归纳,还对目标检测算法的落地效果做了总结,特别是生活与科技中的实际应用(无人驾驶、医学图像、遥感等)。最后,还对深度学习驱动下目标检测在未来研究上的机遇和挑战作了展望。

关键词：目标检测卷积神经网络单阶段两阶段目标检测应用

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An aero-engine life-cycle maintenance policy optimization algorithm: Reinforcement learning approach

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Chinese Journal of Aeronautics 2019年第9期32卷 2133-2150页

作者： Zhen li Shisheng ZHONG lin lin School of Mechatronics Engineering Harbin Institute of Technology

An aero-engine maintenance policy plays a crucial role in reasonably reducing maintenance cost. An aero-engine is a type of complex equipment with long service-life. In engineering,a hybrid maintenance strategy is adopted to improve the aero-engine operational reliability. Thus,the long service-life and the hybrid maintenance strategy should be considered synchronously in aero-engine maintenance policy optimization. This paper proposes an aero-engine life-cycle maintenance policy optimization algorithm that synchronously considers the long service-life and the hybrid maintenance strategy. The reinforcement learning approach was adopted to illustrate the optimization framework, in which maintenance policy optimization was formulated as a Markov decision process. In the reinforcement learning framework, the Gauss–Seidel value iteration algorithm was adopted to optimize the maintenance policy. Compared with traditional aero-engine maintenance policy optimization methods, the long service-life and the hybrid maintenance strategy could be addressed synchronously by the proposed algorithm. Two numerical experiments and algorithm analyses were performed to illustrate the optimization algorithm in detail.

关键词： Aero-engine Hybrid strategy Maintenance policy Optimization algorithm Reinforcement learning

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Insights on the solubilization products after combined alkaline and ultrasonic pre-treatment of sewage sludge

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Journal of Environmental Sciences 2015年第3期27卷 97-105页

作者： Xinbo Tian Chong Wang Antoine Prandota Trzcinski leonard lin Wun Jern Ng Advanced Environmental Biotechnology Centre Nanyang Environment and Water Research Institute Nanyang Technological University School of Civil and Environmental Engineering Nanyang Technological University Public Utilities Board Water Reclamation (Plants) Department Nanyang Environment and Water Research Institute Nanyang Technological University

This work provides insights on the solubilization products after a simultaneous combination of alkaline and ultrasonic （ALK ＋ ULS） pre-treatment of sewage sludge. Soluble chemical oxygen demand （SCOD） increased from 1200 to 11,000 mg/L after such treatment. Organics with molecular weight around 5.6 kDa were solubilized because of the synergistic effect of ultrasound and alkali. Organics with molecular weight larger than 300 kDa increased from 7.8% to 60%, 16% and 42.3% after ULS, ALK and ALK ＋ ULS treatment, respectively. Excitation emission matrix fluorescence spectroscopy analysis identified soluble microbial product-like and humic acid-like matters as the main solubilization products. Sludge anaerobic biodegradability was significantly enhanced with the simultaneous application of ALK ＋ ULS pre-treatment. ALK ＋ ULS pre-treatment resulted in 37.8% biodegradability increase compared to the untreated sludge. This value was higher compared to the biodegradability increase induced by individual ALK pre-treatment （5.7%） or individual ULS pre-treatment （20.7%） under the same conditions applied.

关键词： Ultrasound AlkaliSewage sludge Molecular weight Excitation emission matrix (EEM) Anaerobic biodegradability

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Selective photosynthesis of imines from biomass-derived aldehydes over Ni/TiO_(2)

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Rare Metals 2024年第3期43卷 1116-1124页

作者： Wu-lin li Qing-Qing Zhang lin Dong Wen-Jun Zhang li-li lin Zu-Peng Chen Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources International Innovation Center for Forest Chemicals and MaterialsCollege of Chemical EngineeringNanjing Forestry UniversityNanjing210037China Institute of Industrial Catalysis State Key Laboratory of Green Chemistry Synthesis TechnologyCollege of Chemical EngineeringZhejiang University of TechnologyHangzhou310014China

Photocatalytic reductive amination of biomass-derived aldehydes is a desirable way to selectively upgrade biomass into value-added nitrogen-containing chemicals under mild ***,it is challenging to produce imines in high selectivity because of the undesirable side reactions caused by the activity of functional ***,we demonstrate the highly reactive and selective production of imines from biomass derived aldehydes via the photocatalytic reductive amination,using a defective TiO_(2)supported nickel *** employment of methanol as the hydrogen donor and ammonia solution as the nitrogen source avoids the use of high-pressure H_(2)and expensive amines,rendering the current catalytic process safe,economical,and environmentally *** depth investigations attribute the improved separation and transfer of photogenerated charge carriers to the presence of oxygen vacancies and decorated Ni nanoparticles,thereby accelerating the production of imines from benzaldehyde amination(conversion,95.8%;seleetivity,95.2%).Furthermore,the developed system could be easily translated to the photocatalytic conversions of various biomass derived aldehydes,which provided an example of a cost-effective and sustainable approach for the valorization of biomass derived feedstocks.

关键词： Photocatalysis Biomass derivatives Imines Reduction amination Heterogeneous catalyst

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基于教学评一体的小学语文作业设计与实施策略

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黄冈师范学院学报 2025年第1期45卷 58-62页

作者：李继林洛阳市涧西英语学校河南洛阳471003

作业设计与实施的质量是评价教学成效的关键指标,同时也是培养学生核心素养的关键要素。在当前小学语文作业设计实践中,存在着对“学”的主体性忽略、对“学”的全程性忽视、对“学”的差异性缺失以及对“评”的效能性丧失等问题。基于... 详细信息

作业设计与实施的质量是评价教学成效的关键指标,同时也是培养学生核心素养的关键要素。在当前小学语文作业设计实践中,存在着对“学”的主体性忽略、对“学”的全程性忽视、对“学”的差异性缺失以及对“评”的效能性丧失等问题。基于教学评价一体的理论框架,本研究以生为本,以目标为导向,以差异性为关键,提出紧扣单元目标,聚焦单元作业整体性;着眼全程陪伴,扩大作业辐射力;丰富作业形式,助力核心素养培养;优化多元评价,提升学生目标感等实施路径,旨在持续提升作业设计与实施的有效性。

关键词：小学语文作业设计教学评一体策略

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