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A Probabilistic Approach for Predicting Vessel Motion

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1877-1879页

作者： Qi Hu Jingyi Liu Zongyu Zuo 7th Research Division Beihang University(BUAA)Beijing 100191China 54th Research Institute of china Electronics Technology Group corporation Shijiazhuang 050081China

Dear Editor,This letter addresses the challenge of forecasting the motion of real-world vessels over an extended period with a limited amount of available *** employing stochastic differential equation(SDE)modeling,we integrate both deterministic and stochastic components of the available ***,we establish a recursive prediction methodology based on Bayes’rule to update the model state when new measurements are ***,we develop a stochastic model tailored specifically to vessel dynamics and introduce an approximation method to tackle computational ***,we present an application example and conduct a comparative experiment to validate the effectiveness and superiority of the proposed method.

关键词： method stochastic letter

单轴压缩条件下新型岩石损伤本构模型及应力阈值定量识别新方法（英文）

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Journal of Central South University 2024年第8期 2658-2675页

作者：杜坤易阳罗鑫尧刘凯李鹏王少锋 School of Resources and Safety Engineering Central South University Zhongnan Engineering corporation limited Power Construction Corporation of China

岩石在压缩过程中存在4个关键应力阈值,即裂纹闭合应力(σcc)、裂纹起裂应力(σci)、裂纹损伤应力(σcd)和抗压强度（σc）。前三个应力阈值的定量识别对于表征岩石在压缩作用下的微裂纹扩展和损伤演化具有重要意义。本文提出了一种基... 详细信息

岩石在压缩过程中存在4个关键应力阈值,即裂纹闭合应力(σcc)、裂纹起裂应力(σci)、裂纹损伤应力(σcd)和抗压强度（σc）。前三个应力阈值的定量识别对于表征岩石在压缩作用下的微裂纹扩展和损伤演化具有重要意义。本文提出了一种基于损伤本构模型的岩石应力阈值定量测量方法。首先,考虑岩石的压实阶段和损伤单元的承载能力,基于声发射计数和Weibull分布函数建立了两种不同的损伤本构模型;然后,引入累积声发射计数法（ACLM）、声发射计数率法（CRM）和本构模型法（CMM）确定岩石的应力阈值;最后,利用ACLM、CRM和CMM识别了9种不同岩石的应力阈值。结果表明,两种损伤本构模型的理论应力-应变曲线与试验数据吻合较好,两种损伤本构模型的差异主要来自损伤变量的演化差异。CMM法确定的应力阈值与声发射方法（ACLM和CRM）确定的应力阈值吻合较好。因此,所提出的CMM法可用于确定岩石的应力阈值。

关键词：应力阈值声发射损伤本构模型损伤单元定量方法

High corrosion and wear resistant electroless Ni–P gradient coatings on aviation aluminum alloy parts

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 155-164页

作者： Bo Wang Jiawei Li Zhihui Xie Gengjie Wang Gang Yu College of Chemistry and Chemical Engineering Hunan UniversityChangsha 410012China Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province/College of Chemistry and Chemical Engineering China West Normal UniversityNanchong 637002China Zhongchuan Machinery Ltd.Co. Aero Engine Corporation of ChinaChangsha 410200China

A Ni–P alloy gradient coating consisting of multiple electroless Ni–P layers with various phosphorus contents was prepared on the aviation aluminum alloy. Several characterization and electrochemical techniques were used to characterize the different Ni–P coatings’ morphologies, phase structures, elemental compositions, and corrosion protection. The gradient coating showed good adhesion and high corrosion and wear resistance, enabling the application of aluminum alloy in harsh environments. The results showed that the double zinc immersion was vital in obtaining excellent adhesion (81.2 N). The optimal coating was not peeled and shredded even after bending tests with angles higher than 90°and was not corroded visually after 500 h of neutral salt spray test at 35℃. The high corrosion resistance was attributed to the misaligning of these micro defects in the three different nickel alloy layers and the amorphous structure of the high P content in the outer layer. These findings guide the exploration of functional gradient coatings that meet the high application requirement of aluminum alloy parts in complicated and harsh aviation environments.

关键词： aluminum alloy electroless nickel coating corrosion adhesion

Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-Wen Sun Fu-Shan Wang Yan Gao Fu-Qing Wei Jia-Chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical corporation of Petrochina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation

Hybrid Beamforming Design and Signal Processing with Fully-Connected Architecture for mmWave Integrated Sensing and Communications

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Journal of Communications and Information Networks 2024年第2期9卷 151-161页

作者： Hongyu Li Jun Gong Wenchi Cheng The 54th Research Institute of china Electronics Technology Group corporation Shijiazhuang 050080China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China

Millimeter-wave (mmWave) is capable of achieving gigabit/second communication capacity and centimeter-level sensing accuracy and has become one of the main frequency bands for integrated sensing and communications (ISAC) research. Hybrid beamforming techniques have attracted much attention for solving the high path loss of mmWave and further reducing the hardware cost of the system. However, the related studies based on multicarrier and fully-connected hybrid architectures are still limited. For this reason,this paper investigates the orthogonal frequency division multiplexing (OFDM) based mmWave fully-connected hybrid architecture ISAC system to form a stable communication beam and dynamically varying sensing beam. In order to realize the aforementioned multifunctional beams, the hybrid beamformer design problem based on weighted error minimization of multicarrier is proposed and solved efficiently using the penalty dual decomposition (PDD) algorithm. Meanwhile, based on the echo model, the multicarrier multiple signal classification (MUSIC) algorithm for target angle of arrival estimation and the two-dimensional discrete Fourier transform(2D-DFT)algorithm for distance and velocity estimation are proposed, respectively. Numerical simulation results show that by adjusting the weighting factor,a flexible trade-off can be formed between the communication spectrum efficiency and the sensing accuracy error.

关键词： integrated sensing and communications hybrid beamforming fully-connected architecture millimeter-wave

Study on the pattern of train arrival headway time in high-speed railway

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Railway Sciences 2024年第3期3卷 344-366页

作者： Changhai Tian Shoushuai Zhang Railway Science and Technology Research and Development Center China Academy of Railway Sciences Corporation LimitedBeijingChina School of transportation and logistics Southwest Jiaotong UniversityChengduChina

Purpose-The design goal for the tracking interval of high-speed railway trains in china is 3 min,but it is difficult to achieve,and it is widely believed that it is mainly limited by the tracking interval of train *** the train arrival tracking interval can be compressed,it will be beneficial for china's high-speed railway to achieve a 3-min train tracking *** goal of this article is to study how to compress the train arrival tracking ***/methodologylapproach-By simulating the process of dense train groups arriving at the station and stopping,the headway between train arrivals at the station was calculated,and the pattern of train arrival headway was obtained,changing the traditional understanding that the train arrival headway is considered the main factor limiting the headway of ***-When the running speed of trains is high,the headway between trains is short,the length of the station approach throat area is considerable and frequent train arrivals at the station,the arrival headway for the first group or several groups of trains will exceed the headway,but the subsequent sets of trains will havea headway equal to the arrival *** convergence characteristic is obtained by appropriately increasing the running ***/value-According to this pattern,there is no need to overly emphasize the impact of train arrival headway on the *** plays an important role in compressing train headway and improving high-speedrailwaycapacity.

关键词： High speed railway Train headway Train arrival headway Regular pattern Paper type Research paper

Blockade of CD300A enhances the ability of human NK cells to lyse hematologic malignancies

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Cancer Biology & Medicine 2024年第4期21卷 331-346页

作者： Shuangcheng Li Tianci Wang Xinghui Xiao Xiaodong Zheng Haoyu Sun Rui Sun Hongdi Ma Zhigang Tian Xiaohu Zheng Hefei National Research Center for Physical Sciences at Microscale The CAS Key Laboratory of Innate Immunity and Chronic DiseaseSchool of Basic Medical SciencesCenter for Advanced Interdisciplinary Science and Biomedicine of IHMDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China Institute of Immunology University of Science and Technology of ChinaHefei 230027China Hefei TG ImmunoPharma corporation limited Hefei 230601China Research Unit of NK Cell Study Chinese Academy of Medical SciencesBeijing 100864China Key Laboratory of Quantitative Synthetic Biology Shenzhen Institute of Synthetic BiologyShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Objective: The human cluster of differentiation(CD)300A, a type-I transmembrane protein with immunoreceptor tyrosine-based inhibitory motifs, was investigated as a potential immune checkpoint for human natural killer(NK) cells targeting hematologic malignancies(HMs).Methods: We implemented a stimulation system involving the CD300A ligand, phosphatidylserine(PS), exposed to the outer surface of malignant cells. Additionally, we utilized CD300A overexpression, a CD300A blocking system, and a xenotransplantation model to evaluate the impact of CD300A on NK cell efficacy against HMs in in vitro and in vivo settings. Furthermore, we explored the association between CD300A and HM progression in ***: Our findings indicated that PS hampers the function of NK cells. Increased CD300A expression inhibited HM lysis by NK cells. CD300A overexpression shortened the survival of HM-xenografted mice by impairing transplanted NK cells. Blocking PS–CD300A signals with antibodies significantly amplified the expression of lysis function-related proteins and effector cytokines in NK cells, thereby augmenting the ability to lyse HMs. Clinically, heightened CD300A expression correlated with shorter survival and an “exhausted” phenotype of intratumoral NK cells in patients with HMs or solid ***: These results propose CD300A as a potential target for invigorating NK cell-based treatments against HMs.

关键词： NK cell CD300A phosphatidylserine immune checkpoint hematologic malignancy

Impact of typical environments in china’s western mountainous areas on the durability of railway concrete:a review

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Railway Sciences 2024年第5期3卷 650-669页

作者： Jiahe Wang Yanbin Tan Huajian Li Xinhua Zhong Jiaxuan Wang Yu Gao china Academy of Railway Sciences corporation limited Railway Engineering Research InstitutionBeijingChina and State Key Laboratory of High Speed Railway Track SystemBeijingChina

Purpose–This study aims to analyze the impact mechanism of typical environments in china’s western mountainous areas on the durability of railway concrete and propose measures to improve ***/methodology/approach–With the continuous promotion of infrastructure construction,the focus of china’s railway construction has gradually shifted to the western *** four typical environments of large temperature differences,strong winds and dryness,high cold and low air pressure unique to the western mountainous areas of china have adverse effects on the durability of typical railway structure concrete(bridges,ballastless tracks and tunnels).This study identified the characteristics of four typical environments in the western mountainous areas of china through on-site *** impact mechanism of the four typical environments on the durability of concrete in different structural parts of railways has been explored through theoretical analysis and experimental research;Finally,a strategy for improving the durability of railway concrete suitable for the western mountainous areas of china was ***–The daily temperature difference in the western mountainous areas of china is more than twice that of the plain region,which will lead to significant temperature deformation and stress in the multi-layered structure of railway ballastless *** will result in *** wind speed in the western plateau region is about 2.5 to 3 times that of the plain region,and the average annual rainfall is only 1/5 of that in the plain *** drying effect on the surface of casting concrete will significantly accelerate its cracking process,leading to serious durability *** environmental temperature in the western mountainous areas of china is generally low,and there are more freeze-thaw cycles,which will increase the risk of freeze-thaw damage to railway *** environmental air pressure in the western plateau region is only 60%of that in

关键词： Western mountainous areas Concrete Durability Environment

Research on the evolution law of dynamic performance of CR400BF EMU train based on stochastic dynamics simulation

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Railway Sciences 2024年第2期3卷 143-155页

作者： Di Cheng Yuqing Wen Zhiqiang Guo Xiaoyi Hu Pengsong Wang Zhikun Song Railway Science and Technology Research and Development Center China Academy of Railway Sciences Corporation LimitedBeijingChina School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijingChina

Purpose–This paper aims to obtain the evolution law of dynamic performance of CR400BF electric multiple unit(EMU).Design/methodology/approach–Using the dynamic simulation based on field test,stiffness of rotary arm nodes and damping coefficient of anti-hunting dampers were ***,damping coefficient,friction coefficient,track gauge were taken as random variables,the stochastic dynamics simulation method was constructed and applied to research the evolution law with running mileage of dynamic index of CR400BF ***–The results showed that stiffness and damping coefficient subjected to normal distribution,the mean and variance were computed and the evolution law of stiffness and damping coefficient with running mileage was ***/value–Firstly,based on the field test we found that stiffness of rotary arm nodes and damping coefficient of anti-hunting dampers subjected to normal distribution,and the evolution law of stiffness and damping coefficient with running mileage was *** stiffness,damping coefficient,friction coefficient,track gauge were taken as random variables,the stochastic dynamics simulation method was constructed and applied to the research to the evolution law with running mileage of dynamic index of CR400BF EMU.

关键词： Vehicle system dynamics Stiffness of rotary arm nodes Anti-snaking damper damping Random variable