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Effects of Heat Softening on Initiation of Landslides

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Journal of Mountain Science 2014年第6期11卷 1571-1578页

作者： XIONG Chuan-xiang lu xiao-bing HUANG Wei-da WANG Cheng-hua School of Environment and Resources Fuzhou University Fujian Provincial Key Laboratory of Remote Sensing of Soil Erosion and Disaster Protection Institute of Mechanics Chinese Academy of Sciences Fujian Academy of Building Research Institute of Mountain Hazards and Environment Chinese Academy of Sciences

Effects of heat softening on the initiation of slide surface(shear banding) in clayey slopes during fast deformation were *** equations considering heat,pore pressure and mechanical movement were *** perturbation method,the instability condition of localized zone(*** for initiation of shear banding) for thermal related soils,such as clayey slope,was *** is shown that slide surface initiates once the thermal-softening effects overcome the strain-hardening effects whether it is adiabatic or *** strain hardening effects,strain rate hardening obviously plays a role in initiation of shear *** initiating process,heat is trapped inside the shear band,which leads rapidly to a pore pressure increase and fast loss of *** localized shear strain is concentrated in a narrow zone with a width of several centimeters at most and increases *** zone forms the sliding *** can increase more than 2?C,pore pressure can increase 160% in about 0.1s inside this *** changes cause the fast decrease in friction-coefficient by about 36% over the initial *** is how shear band initiated and developed in clayey slopes.

关键词： Landslide Thermo-effect Slide surface Initiation

孕11～13^(+6)周超声筛查胎儿21-三体综合征的研究

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苏州大学学报（医学版） 2009年第4期29卷 691-693页

作者：梁青邓学东殷林亮姜小力陆冰孙玲玲苏州市立医院母子保健中心超声科江苏苏州215002

目的探讨孕11～13+6周(胎儿头臀长45~84mm)超声筛查胎儿21-三体综合征的可行性。方法随机对3000例孕中2342例孕11～13+6周的胎儿进行超声筛查,早孕期鼻骨均做"有或无"的鉴定。结果鼻骨缺失的胎儿21-三体综合征的阳性预测值达50%;孕早期... 详细信息

目的探讨孕11～13+6周(胎儿头臀长45~84mm)超声筛查胎儿21-三体综合征的可行性。方法随机对3000例孕中2342例孕11～13+6周的胎儿进行超声筛查,早孕期鼻骨均做"有或无"的鉴定。结果鼻骨缺失的胎儿21-三体综合征的阳性预测值达50%;孕早期鼻骨长度与颈项透明层厚度(NT)之间无相关性;孕早期鼻骨长度与双顶径呈线性增长。结论孕早期鼻骨的缺失对21-三体综合征有较高的阳性预测值,一旦超声诊断鼻骨缺失,均应进行细胞学检查;鼻骨与NT作为预测21-三体综合征风险的独立因素,孕早期鼻骨长度与双顶径呈线性增长,孕早期鼻骨的长度对预测21-三体综合征没有意义。

关键词：孕11~13+6周超声筛查 21-三体综合征

Relativistic calculations on the transition electric dipole moments and radiative lifetimes of the spin-forbidden transitions in the antimony hydride molecule

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Chinese Physics B 2022年第8期31卷 125-130页

作者： Yong Liu lu-lu Li Li-Dan xiao bing Yan Institute of Atomic and Molecular Physics Jilin UniversityChangchun 130012China

Calculations on the spectroscopic constants and transition properties of the first three states(a^(1)△,b^(1)Σ^(+),and X3Σ-)of the Sb H molecule were performed under the relativistic framework using the exact two-component Hamiltonian(X2C).The potential energy curves in the Franck-Condon region were computed and compared with the previous ***,the transition dipole moments for the weak spin-forbidden transitions(b0^(+)-X10^(+),b0^(+)-X_(2)1,X10^(+)-X_(2)1,and X_(2)1-a2)were *** spontaneous radiative lifetime of the b1Σ^(+)(υ′=0)state was calculated as 163.5±7.5μs,which is in reasonable agreement with the latest experimental value of 173±3μ*** spontaneous radiative lifetimes of the X_(2)1(υ′=0)state and the a2(υ′=0)state were calculated to be 48.6 s and~8 ms,*** study is expected to be a benchmark transition property computation for comparison with other theoretical and experimental *** datasets presented in this paper,including the transition dipole moments,are openly available at https://***/10.11922/sciencedb.j00113.00018.

关键词： Sb H transition properties radiative lifetimes

Cross-subcarrier precoder design for massive MIMO-OFDM downlink with symplectic optimization

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Science China(Information Sciences) 2025年

作者： Yu-Xuan ZHANG An-An lu Xiang-Gen XIA Xi-Qi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Electrical and Computer Engineering University of Delaware

We propose a cross-subcarrier precoder design(CSPD) for massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) downlink. This work aims to significantly improve the channel estimation and signal detection performance by enhancing the smoothness of the frequency domain effective channel. This is accomplished by designing a few vectors known as the transform domain precoding vectors(TDPVs), which are then transformed into the frequency domain to generate the precoders for a set of subcarriers. To combat the effect of channel aging, the TDPVs are optimized under imperfect channel state information(CSI). The optimal precoder structure is derived by maximizing an upper bound of the ergodic weighted sum-rate(WSR) and utilizing the a posteriori beam-based statistical channel model(BSCM). To avoid the large-dimensional matrix inversion, we propose an algorithm with symplectic optimization. Simulation results indicate that the proposed cross-subcarrier precoder design significantly outperforms conventional methods.

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不同防疫阶段下应急医疗物资调度模型

物流科技 2025年第1期48卷 83-88页

作者：叶露李弘郭冰浙江理工大学经济管理学院浙江杭州310018

比较了异常紧急、紧急、常态下,基于两种紧急度计算形式得到的模型仿真结果,在模型建立的基础上,给出了两期对医用防护服、N95口罩的分配方案。结果表明:选择恰当的紧急度计算形式,所构建的模型能在三种防疫阶段下均能确保多需求点之间... 详细信息

比较了异常紧急、紧急、常态下,基于两种紧急度计算形式得到的模型仿真结果,在模型建立的基础上,给出了两期对医用防护服、N95口罩的分配方案。结果表明:选择恰当的紧急度计算形式,所构建的模型能在三种防疫阶段下均能确保多需求点之间物资分配的公平性,降低需求点在某一阶段产生较大的物资短缺损失的可能,使得应急物资分配更合理。

关键词：最优化理论应急物资需求满足率调度模型

A Novel Self-Supervised Learning Network for Binocular Disparity Estimation

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 209-229页

作者： Jiawei Tian Yu Zhou xiaobing Chen Salman A.AlQahtani Hongrong Chen Bo Yang Siyu lu Wenfeng Zheng Department of Computer Science and Engineering Major in Bio Artificial IntelligenceHanyang UniversityAnsan-si15577Republic of Korea School of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11574Saudi Arabia School of Automation University of Electronic Science and Technology of ChinaChengdu610054China

Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical *** study proposes a novel end-to-end disparity estimation model to address these *** approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting *** study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and *** model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video *** results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing ***,the model exhibited faster convergence during training,contributing to overall performance *** study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.

关键词： Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation

cGAS-STING: mechanisms and therapeutic opportunities

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Science China Life Sciences 2025年

作者： Mengyuan Zhang Changxin Wu Defen lu Xing Wang Guijun Shang Shanxi Medical University School and Hospital of Stomatology Shanxi Province Key Laboratory of Oral Diseases Prevention and New Materials The Key Laboratory of Medical Molecular Cell Biology of Shanxi Province Institutes of Biomedical Sciences Shanxi University College of Life Sciences Shanxi Agricultural University

The cGAS-STING pathway plays a crucial role in the innate immune system by detecting mislocalized double-stranded DNA(dsDNA) in the cytoplasm and triggering downstream signal transduction. Understanding the mechanisms by which cGAS and STING operate is vital for gaining insights into the biology of this pathway. This review provides a detailed examination of the structural features of cGAS and STING proteins, with a particular emphasis on their activation and inhibition mechanisms. We also discuss the novel discovery of STING functioning as an ion channel. Furthermore, we offer an overview of key agonists and antagonists of cGAS and STING, shedding light on their mechanisms of action. Deciphering the molecular intricacies of the cGAS-STING pathway holds significant promise for the development of targeted therapies aimed at maintaining immune homeostasis within both innate and adaptive immunity.

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An Enhanced Dual-Layer Ensemble Framework for Porosity Prediction Utilizing Conventional Well Logging Data

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Journal of Earth Science 2025年

作者： lu Qiao Shengyu Yang Qinhong Hu Huijun Wang Taohua He National Key Laboratory of Deep Oil and Gas， China University of Petroleum (East China) Laboratory for Marine Mineral Resources， Qingdao National Laboratory for Marine Science and Technology Hubei Key Laboratory of Petroleum Geochemistry and Environment (Yangtze University)， Yangtze University

Porosity is the one of the most fundamental and critical parameters for reservoir characterization and is closely related to the hydrocarbon storage capacity. The interpretation methods of conventional well logs have poor generalization capabilities to achieve the desired accuracy in porosity prediction. The increasing adoption of machine learning has ameliorated this predicament to some extent， but it remains difficult to reconstruct the complex and nonlinear relationship between logging responses and porosity by relying on individual machine learning models alone. This work proposes a two-layer model ensemble framework to predicte porosity， which includes base regressors in the first layer and meta regressor in the second layer. The results indicate that the Light Gradient Boosting Machine (LightGBM) - Categorical-Features Gradient Boosting (CatBoost) ensemble model provides the highest prediction accuracy for the given dataset and is applied for porosity evaluation at other logged depths. This work also points out that the base regressor should be accurate and complex， while the structure of the meta-regressor should be simple in order to achieve the desired performance. Furthermore， the proposed model ensemble framework is versatile and applicable to reservoir evaluation， engineering development， and other potential fields due to its effectiveness and convenience.

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Thermoresponsive helical dendronized poly(arylacetylene)s:modulating the dynamic chirality

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Science China Chemistry 2025年

作者： Xueting lu Lei Wang Liangxuan Ren Wen Li Afang Zhang International Joint Laboratory of Biomimetic&Smart Polymers School of Materials Science and EngineeringShanghai University

Helical poly(arylacetylene)s have formed an intriguing class of polymers,whose chiralities are dynamic and liable to external *** combining dendronized polymer topology with dendritic oligoethylene glycols (OEGs),we here report on synthesis of a homologous series of thermoresponsive dendronized poly(arylacetylene)s with either poly(phenyl acetylene) or poly(naphthalene acetylene) as the backbones,and investigate tunability of their helical *** polymers carry dendritic OEG pendants with either methoxyl-or ethoxyl-terminals to tune their unprecedent thermoresponsive behaviors,and at the same time,dendritic shielding plays an important role in mediating their thermal phase transition *** of these polymers is originated from the chiral alanine or phenylalanine moieties within the dendritic pendants,which can be tailored through manipulating solvation in different organic solvents or via thermal dehydration and collapse in ***,achiral additives such as linear or dendritic OEGs and benzene derivatives can act similarly as thermal dehydration to induce chirality transitions of these polymers in aqueous phase through interplay competitions between the additives and the polymers against their hydration.

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