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Laboratory-scale investigation of the material distribution characteristics of landslide dams in U-shaped valleys

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Journal of Mountain Science 2023年第3期20卷 688-704页

作者： JIAN Fu-xian cai zheng-yin GUO Wan-li Geotechnical Engineering Department Nanjing Hydraulic Research InstituteNanjing 210024China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing 210024China

Material distribution characteristics during sliding and depositing is particularly significative to investigate the internal structure and spatial variation of landslide dams,which are fundamentally determining the mechanical and hydraulic behavior and the susceptibility to cause dam ***,limited by longevity shortages and special geographic environments,the material distribution characteristics and their formation mechanisms are difficult to observe in the ***,an experimental apparatus modeling a landslide dam was developed in this paper,designing three sampling methods with two valley *** internal deposit characteristics,void ratio variation and relative content of the particle size range(PSR)were analyzed,and the mechanics of deposit structure were also delicately *** results indicate that granular material deposited in valley shows a structure of inverse grain size accumulation in both vertical and horizontal directions,exhibiting spatial variability of particle gradation and void *** characteristic PSR decreases from 22-30 mm in the two-dimensional state to 10-14 mm in the threedimensional *** excitation and vibration sieve are the intrinsic mechanisms of granular flow segregation,intrinsically inducing the formation of inverse grading deposit ***,spatial variability in size is mainly trig gered by segregation,whereas coarse particle content and deposition boundaries merely exacerbate the difference degree.

关键词： Landslide dam IInverse grading structure Granular flow segregation Material spatial variability Deposit characteristics

PAL-BERT:An Improved Question Answering Model

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Computer Modeling in Engineering & Sciences 2024年第6期139卷 2729-2745页

作者： Wenfeng zheng Siyu Lu Zhuohang cai Ruiyang Wang Lei Wang Lirong yin School of Automation University of Electronic Science and Technology of ChinaChengdu610054China Department of Geography and Anthropology Louisiana State UniversityBaton RougeLA70803USA

In the field of natural language processing(NLP),there have been various pre-training language models in recent years,with question answering systems gaining significant ***,as algorithms,data,and computing power advance,the issue of increasingly larger models and a growing number of parameters has ***,model training has become more costly and less *** enhance the efficiency and accuracy of the training process while reducing themodel volume,this paper proposes a first-order pruningmodel PAL-BERT based on the ALBERT model according to the characteristics of question-answering(QA)system and language ***,a first-order network pruning method based on the ALBERT model is designed,and the PAL-BERT model is ***,the parameter optimization strategy of the PAL-BERT model is formulated,and the Mish function was used as an activation function instead of ReLU to improve the ***,after comparison experiments with traditional deep learning models TextCNN and BiLSTM,it is confirmed that PALBERT is a pruning model compression method that can significantly reduce training time and optimize training *** with traditional models,PAL-BERT significantly improves the NLP task’s performance.

关键词： PAL-BERT question answering model pretraining language models ALBERT pruning model network pruning TextCNN BiLSTM

Optimization of resource allocation in FDD massive MIMO systems

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Digital Communications and Networks 2024年第1期10卷 117-125页

作者： Jun cai Chuan yin Youwei Ding School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing 210046China School of Electronic and Information Hangzhou Dianzi UniversityHangzhou 310018ZhejiangChina

The performance of massive MIMO systems relies heavily on the availability of Channel State Information at the Transmitter(CSIT).A large amount of work has been devoted to reducing the CSIT acquisition overhead at the pilot training and/or CsI feedback *** fact,the downlink communication generally includes three stages,i.e.,pilot training,CsI feedback,and data *** three stages are mutually related and jointly determine the overall system ***,there exist few studies on the reduction of csIT acquisition overhead from the global point of *** this paper,we integrate the Minimum Mean Square Error(MMSE)channel estimation,Random Vector Quantization(RVQ)based limited feedback and Maximal Ratio Combining(MRC)precoding into a unified framework for investigating the resource allocation *** particular,we first approximate the covariance matrix of the quantization error with a simple expression and derive an analytical expression of the received Signal-to-Noise Ratio(SNR)based on the deterministic equivalence *** the three performance metrics(the spectral efficiency,energy efficiency,and total energy consumption)oriented problems are formulated *** practical system requirements,these three metrics can be collaboratively ***,we propose an optimization solver to derive the optimal partition of channel coherence *** results verify the benefits of the proposed resource allocation schemes under three different scenarios and illustrate the tradeoff of resource allocation between three stages.

关键词： Massive MIMO FDD CSIT Resource allocation

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砂土的渐进破坏及其数值模拟

岩土力学 2008年第3期29卷 580-585页

作者：蔡正银南京水利科学研究院岩土工程研究所南京210024

紧密砂土在排水剪切过程中由于材料的应变软化特性,会出现变形局部化并伴随剪切带的产生。对此类问题进行数值模拟时会遇到很多困难,比如如何模拟紧砂的应变软化特性,如何处理有限元数值分析过程中刚度矩阵的非正定导致计算结果发散问题... 详细信息

紧密砂土在排水剪切过程中由于材料的应变软化特性,会出现变形局部化并伴随剪切带的产生。对此类问题进行数值模拟时会遇到很多困难,比如如何模拟紧砂的应变软化特性,如何处理有限元数值分析过程中刚度矩阵的非正定导致计算结果发散问题,以及如何处理应力不连续的问题,拟针对以上问题进行了探讨。

关键词：砂土变形局部化应变软化数值模拟

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板桩结构土压力理论的创新发展

岩土工程学报 2020年第2期42卷 201-220页

作者：蔡正银南京水利科学研究院岩土工程研究所江苏南京210024

对于板桩码头,其主要的荷载为作用于码头前墙上的土压力,该荷载一方面是由于港池开挖引起前墙两侧土压力的不平衡产生,另一方面是由于码头表面荷载作用于地基土,从而增加了前墙陆侧的土压力。板桩码头深水化的关键要求必须解决港池挖深... 详细信息

对于板桩码头,其主要的荷载为作用于码头前墙上的土压力,该荷载一方面是由于港池开挖引起前墙两侧土压力的不平衡产生,另一方面是由于码头表面荷载作用于地基土,从而增加了前墙陆侧的土压力。板桩码头深水化的关键要求必须解决港池挖深导致的前墙土压力急剧增大问题,"遮帘"和"卸荷"是减少前墙土压力的有效途径,由于设置了遮帘桩和卸承台,使得板桩结构的受力情况更加复杂,涉及的关键科学技术问题是土和结构的相互作用。针对遮帘式和分离卸荷式板桩码头新结构开发过程中的土压力问题,先后研究了土体密度与粒径对静止土压力系数的影响、遮帘式板桩结构的土压力"桶仓压力效应"和"遮帘效应",以及分离卸荷式板桩结构的土压力"卸荷效应",为板桩码头新结构的发展奠定了理论基础。

关键词：板桩土压力桶仓效应遮帘效应卸荷效应离心模型试验

Platelet-based bioactive systems guided precision targeting and immune regulation for cancer therapy

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Nano Research 2024年第9期17卷 8269-8284页

作者： Xinyi cai Long Qiu Zhenying Diao Lintao cai Ting yin Hong Pan Guangdong Key Laboratory of Nanomedicine CAS-HK Joint Lab of BiomaterialsCAS Key Laboratory of Biomedical Imaging Science and SystemInstitute of Biomedicine and BiotechnologyShenzhen Institute of Advanced Technology(SIAT)Chinese Academy of SciencesShenzhen 518055China School of pharmacy Guangdong Medical UniversityDongguan 523808China Sino-Euro Center of Biomedicine and Health Shenzhen 518024China

The antitumor effects of conventional drug carriers are often attenuated and limited in application by biological barriers associated with tumor heterogeneity and resistance brought about by low tumor *** the rapid development of nanotechnology,naturally derived bioactive materials,and live cell carriers,a promising strategy emerges for targeting the tumor microenvironment(TME)for precision cancer *** unique injury-targeting properties of platelets can significantly extend functional activity,which cannot be achieved with conventional *** this review,three strategies based on platelet-engineered materials are systematically described,namely nanoparticles for platelet membrane camouflage,engineered activated platelets,and targeted-platelets ***-based nanomaterials can effectively coordinate local and distant tumor-host crosstalk with controlled active tumor site recognition and killing effects due to the presence of specific membrane proteins on the surface and the self-secretion of a large number of *** advances in platelets for effectively overcoming biological barriers and reducing immune resistance in cancer immunotherapy applications will be discussed in future clinical *** review provides an overview of recent research advances in platelet-based bioactive material-directed immunotherapy and chemotherapy to inform future antitumor combination therapies.

关键词： platelets bionic targeting immune modulation precision therapy deep penetration

DPAL-BERT:A Faster and Lighter Question Answering Model

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Computer Modeling in Engineering & Sciences 2024年第10期141卷 771-786页

作者： Lirong yin Lei Wang Zhuohang cai Siyu Lu Ruiyang Wang Ahmed AlSanad Salman A.AlQahtani Xiaobing Chen zhengtong yin Xiaolu Li Wenfeng zheng Department of Geography and Anthropology Louisiana State UniversityBaton RougeLA 70803USA School of Automation University of Electronic Science and Technology of ChinaChengdu610054China College of Computer and Information Sciences King Saud UniversityRiyadh11574Saudi Arabia School of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA College of Resources and Environmental Engineering Guizhou UniversityGuiyang550025China School of Geographical Sciences Southwest UniversityChongqing400715China

Recent advancements in natural language processing have given rise to numerous pre-training language models in question-answering ***,with the constant evolution of algorithms,data,and computing power,the increasing size and complexity of these models have led to increased training costs and reduced *** study aims to minimize the inference time of such models while maintaining computational *** also proposes a novel Distillation model for PAL-BERT(DPAL-BERT),specifically,employs knowledge distillation,using the PAL-BERT model as the teacher model to train two student models:DPAL-BERT-Bi and *** research enhances the dataset through techniques such as masking,replacement,and n-gram sampling to optimize knowledge *** experimental results showed that the distilled models greatly outperform models trained from *** addition,although the distilled models exhibit a slight decrease in performance compared to PAL-BERT,they significantly reduce inference time to just 0.25%of the *** demonstrates the effectiveness of the proposed approach in balancing model performance and efficiency.

关键词： DPAL-BERT question answering systems knowledge distillation model compression BERT Bi-directional long short-term memory(BiLSTM) knowledge information transfer PAL-BERT training efficiency natural language processing

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单锚板桩结构的工作机理研究

岩土工程学报 2015年第1期37卷 29-34页

作者：蔡正银侯伟南京水利科学研究院岩土工程研究所江苏南京210024 同济大学地下建筑与工程系上海200092

板桩结构作为支挡建筑物广泛应用于基坑、码头等工程中,其涉及的主要问题是土压力作用下板桩的受力和变形,而土压力与变形又是相互关联的,属于典型的土与结构相互作用问题。以单锚板桩码头结构为例,基于有限元数值模拟,探讨了板桩结构... 详细信息

板桩结构作为支挡建筑物广泛应用于基坑、码头等工程中,其涉及的主要问题是土压力作用下板桩的受力和变形,而土压力与变形又是相互关联的,属于典型的土与结构相互作用问题。以单锚板桩码头结构为例,基于有限元数值模拟,探讨了板桩结构的工作机理,研究了码头港池开挖过程中前墙两侧的土压力分布、结构的内力与变形、地基土的应力应变关系,以及地基不同位置处土单元的主应力旋转等问题。研究表明:正确地模拟土体的应力应变关系是分析此类问题的关键;港池开挖过程中,前墙陆侧土压力向主动方向发展,而海侧土压力则向被动方向发展;港池开挖造成了土体单元的主应力方向旋转,特别是港池海侧下方的土体主应力方向旋转剧烈。

关键词：板桩码头数值模拟土压力主应力方向

Aptamer-Based Antibiotic Electrochemical Detection Platform Using Portable Plastic Gold Electrode and Multichannel Chip

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Chinese Journal of Chemistry 2024年第2期42卷 171-176页

作者： yin Bao Kaiwei cai Yichen Liu Bingling Li Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchunJilin 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefeiAnhui 230026China

The development of accurate,rapid and practical electrochemical sensing technology for antibiotic detection has an important application prospect in many fields such as food safety,environmental monitoring,medical and health *** this research,kanamycin specific DNA aptamer and its partially complementary short chain were self-assembled onto the surface of an integrated portable plastic gold electrode(PGE)by Au-s bond,and a simple kanamycin electrochemical biosensor interface was *** the same time,the epoxy resin channel layer was designed,and the auxiliary instrument was set up independently in the laboratory,which could help to measure and analyze eight groups of samples automatically in *** quantitative analysis results showed that in 20 min,the sensor had a good linear relationship between the peak current change of square wave voltammetry and the negative logarithm of kanamycin concentration when kanamycin concentration was in the range of 1-10o0μmol/L,and the detection limit could reach 0.40μmol/*** addition,the discrimination could be achieved within 5 min in the real-time analysis *** sensor had a simple construction method,good selectivity and stability,and could be used for rapid or real-time detection of kanamycin residues in actual water samples,which provided a new direction for the practical detection of kanamycin in environmental watersamples.

关键词： Biosensor Aptamer Antibiotics Electroanalysis DNA