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波浪影响下水下风筝式AUV建模与力学响应分析

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舰船科学技术 2024年第4期46卷 78-87页

作者：张行健陈质二俞建成任楷陈阔中国科学院沈阳自动化研究所机器人学国家重点实验室辽宁沈阳110016 中国科学院机器人与智能制造创新研究院辽宁沈阳110169 中国科学院大学北京100049

针对强天气条件下相关参数难以获取,提出一种由水面智能拖体、水下高机动AUV和高强度拖缆组成的“水下风筝”式三体AUV,有望实现台风现场海气界面与上层水体同步探测。为探究高海况下“水下风筝”式AUV技术可行性,对其在波浪影响的力学... 详细信息

针对强天气条件下相关参数难以获取,提出一种由水面智能拖体、水下高机动AUV和高强度拖缆组成的“水下风筝”式三体AUV,有望实现台风现场海气界面与上层水体同步探测。为探究高海况下“水下风筝”式AUV技术可行性,对其在波浪影响的力学响应特性进行分析,建立基于微振幅波理论和经典多体刚柔结构动力学建模方法的“水下风筝”式AUV动力学模型,采用数值模拟方法获得了不同拖曳速度、不同海况等级下AUV端受力和深度值,结果表明从力学角度当前技术条件可满足“水下风筝”式AUV高海况下同步观测需求。

关键词： AUV 水下风筝高海况水动力动力学建模

Distance Estimates for Simple Choreographic Solutions of the Three-body Problem

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Acta Mathematica Sinica,English Series 2022年第10期38卷 1823-1830页

作者： kuo Chang chen Bo Yu PAN Department of Mathematics “National Tsing Hua University”HsinchuTaiwanChina Department of Applied Mathematics “National Chung Hsing University”TaichungTaiwanChina

In this article we estimate mutual distances of simple choreographic solutions for the Newtonian three-body *** formulas will be proved and our applications include the famous figure-8 orbit.

关键词： n-body problem variational method mutual distance

Tunable dispersion relations manipulated by strain in skyrmion-based magnonic crystals

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Chinese Physics B 2024年第1期33卷 692-696页

作者：金兆年何宣霖于超方贺男陈琳陶志阔 Bell Honors School Nanjing University of Posts and TelecommunicationsNanjing 210003China College of Electronic and Optical Engineering&College of Flexible Electronics Nanjing University of Posts and TelecommunicationsNanjing 210003China

We theoretically investigate the propagation characteristics of spin waves in skyrmion-based magnonic crystals. It is found that the dispersion relation can be manipulated by strains through magneto-elastic coupling. Especially, the allowed bands and forbidden bands in dispersion relations shift to higher frequency with strain changing from compressive to tensile,while shifting to lower frequency with strain changing from tensile to compressive. We also confirm that the spin wave with specific frequency can pass the magnonic crystal or be blocked by tuning the strains. The result provides an advanced platform for studying the tunable skyrmion-based spin wave devices.

关键词： skyrmion magnonic crystal spin wave dispersion relation

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渗流管涌作用下松散堆积层结构演化规律

科学技术与工程 2024年第9期24卷 3813-3823页

作者：蔡沛辰毛雪松胡仪喣解阔长安大学公路学院西安710064

为揭示渗流管涌作用下松散堆积层结构演化规律,基于颗粒-孔隙尺度流固耦合方法,分别对密实、中密和疏松结构的松散堆积层开展渗流管涌仿真试验,从细观层面分析渗流管涌作用下松散堆积层颗粒迁移特征、颗粒流失量、颗粒间接触力链演化和... 详细信息

为揭示渗流管涌作用下松散堆积层结构演化规律,基于颗粒-孔隙尺度流固耦合方法,分别对密实、中密和疏松结构的松散堆积层开展渗流管涌仿真试验,从细观层面分析渗流管涌作用下松散堆积层颗粒迁移特征、颗粒流失量、颗粒间接触力链演化和骨架变形的结构演化特征。结果表明:渗流管涌主要以细颗粒迁移为主,存在局部“堵塞”现象,块石颗粒仅会在细颗粒迁移脱空后自由堆积。细颗粒迁移具有明显的“颗粒堆积”现象,主要集中在出口处,呈“上多下少”的特点。同时,渗流管涌发展过程中相同部位的孔隙率变化具有高度相似性,且结构越疏松越显著。管涌发展过程中,块石颗粒间接触承担主要的应力传递,力链演化的本质是堆积填料内部应力传递结构的改变。此外,下沉量和体应变均随时步增加,呈先急剧增加,后趋于平稳的态势,且随初始渗流速度越大,平稳时刻逐步提前。该研究成果可为从细观角度认识松散堆积层渗流管涌结构演化规律提供一定借鉴。

关键词：松散堆积层渗流管涌颗粒流力链网络结构演化

Evaluation of different Krylov subspace methods for simulation of the water faucet problem

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Nuclear Science and Techniques 2021年第5期32卷 1-16页

作者： Hong-Yang Wei Kevin Briggs Victor Quintanilla Yi-tung chen Department of Mechanical Engineering University of NevadaLas VegasNV 89154USA

In this study,a one-dimensional two-phase flow four-equation model was developed to simulate the water faucet *** performance of six different Krylov subspace methods,namely the generalized minimal residual(GMRES),transpose-free quasi-minimal residual,quasi-minimal residual,conjugate gradient squared,biconjugate gradient stabilized,and biconjugate gradient,was evaluated with and without the application of an incomplete LU(ILU)factorization preconditioner for solving the water faucet *** simulation results indicate that using the ILU preconditioner with the Krylov subspace methods produces better convergence performance than that without the ILU *** the GMRES demonstrated an acceptable convergence performance under the Krylov subspace methods without the *** velocity and pressure distribution in the water faucet problem could be determined using the Krylov subspace methods with an ILU preconditioner,while GMRES could determine it without the need for a ***,there are significant advantages of using an ILU preconditioner with the GMRES in terms of *** different Krylov subspace methods showed similar performance in terms of computational efficiency under the application of the ILU preconditioner.

关键词： Water faucet problem Krylov subspace methods ILU preconditioner

Out of sight, out of mind: a distance-aware forgetting strategy for adaptive random testing

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Science China(Information Sciences) 2017年第9期60卷 78-98页

作者： chengying MAO Tsong Yueh chen Fei-Ching kuo School of Software and Communication Engineering Jiangxi University of Finance and Economics Department of Computer Science and Software Engineering Swinburne University of Technology

Adaptive random testing(ART) achieves better failure-detection effectiveness than random testing by increasing the diversity of test cases. However, the intention of ensuring even spread of test cases inevitably causes an overhead problem. Although two basic forgetting strategies(i.e. random forgetting and consecutive retention) were proposed to reduce the computation cost of ART, they only considered the temporal distribution of test cases. In the paper, we presented a distance-aware forgetting strategy for the fixed size candidate set version of ART(DF-FSCS), in which the spatial distribution of test cases is taken into consideration. For a given candidate, the test cases out of its "sight" are ignored to reduce the distance computation cost. At the same time, the dynamic adjustment for partitioning and the second-round forgetting are adopted to ensure the linear complexity of DF-FSCS algorithm. Both simulation analysis and empirical study are employed to investigate the efficiency and effectiveness of DF-FSCS. The experimental results show that DF-FSCS significantly outperforms the classical ART algorithm FSCS-ART in efficiency, and has comparable failure-detection effectiveness. Compared with two basic forgetting methods, DF-FSCS is better in both efficiency and effectiveness. In contrast with a typical linear-time ART algorithm RBCVT-Fast, our algorithm requires less computational overhead and exhibits the similar failure-detection capability. In addition, DF-FSCS has more reliable performance than RBCVT-Fast in detecting failures for the programs with high-dimensional input domain.

关键词： adaptive random testing software testing test cases computational overhead diversity

Hydrocarbon pneumonitis following fuel siphonage: A case report and literature review

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World Journal of Emergency Medicine 2019年第2期10卷 69-74页

作者： Yi-jung chen Chien-chin Hsu kuo-tai chen Emergency Department Chi-Mei Medical Center Department of Biotechnology Southern Tainan University of Technology Department of Emergency Medicine School of Medicine College of Medicine Taipei Medical University

BACKGROUND: People sometimes siphon fuel to fill their tanks. However, this is a potentially dangerous procedure and may cause hydrocarbon pneumonitis. We present the case of a patient with severe hydrocarbon pneumonitis after siphoning fuel. The patient underwent artifi cial ventilation and was admitted to hospital for 97 days. METHODS: We review the relevant literature for a better understanding of clinical features and management strategies for hydrocarbon pneumonitis following fuel ***: We reviewed 15 articles, which included 3 original articles and 12 case reports that reported the clinical features of fuel siphonage. In addition, we added our presented case for data analysis. A total of 40 cases were included in this review. The literature review found that hydrocarbon pneumonitis caused by fuel siphonage occurs worldwide and that most patients(80%) became symptomatic within 1 day of aspiration. Cough(70%), chest pain(62.5%), dyspnoea(55%), and fever(52.5%) presented in more than half of all patients. The right middle lobe(80%) was the predominantly involved lung fi eld; more than one-third of patients(36.7%) showed the involvement of two ***: Patient history, computed tomographic scans of the chest, and bronchoalveolar lavage are the commonly used diagnostic tools. Supportive care remains the foundation of treatment, whereas antibiotics, steroids, and bronchoalveolar lavage are practical therapies. Patients' clinical improvement precedes the resolution of lesions on chest X-ray. Most complications arise from pulmonary lesions. The prognosis of patients suffering from hydrocarbon pneumonitis following fuel siphonage might be improved by accurate diagnosis and appropriate care.

关键词： Siphonage Diesel Fuel Aspiration Hydrocarbon pneumonitis

D53 represses rice blast resistance by directly targeting phenylalanine ammonia lyases

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Journal of Integrative Plant Biology 2024年第9期66卷 1827-1830页

作者： Haitao Ye Qingqing Hou Haitao Lv Hui Shi Duo Wang Yujie chen Tangshuai Xu Mei Wang Min He Junjie Yin Xiang Lu Yongyan Tang Xiaobo Zhu Lijuan Zou Xuewei chen Jiayang Li Bing Wang Jing Wang State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China Sichuan Agricultural UniversityChengdu 611130China Key Laboratory of Seed Innovation Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Yazhouwan National Laboratory Sanya 572024China

Phytohormones play important roles in orchestrating plantimmune responses to pathogen ***(SLs),a group of carotenoid-derived phytohormones,modulate diverse biological processes in plants,including shoot branching,plant height,root architecture,leaf senescence,seed germination of parasitic plants,and symbiosis of arbuscular mycorrhizal fungi(Burger and Chory,2020).Recently,increasing evidence has indicated potential roles for SLs in regulating responses against biotic stresses,including defense responses against certain pathogenic fungi and bacteria in roots and leaves(Yi et al.,2023).

关键词： ammonia resistance branching

基于刮涂微结构的柔性电容式触觉传感器特性研究

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传感器与微系统 2024年第1期43卷 48-51页

作者：陈地材刘吉晓王鹏刘阔郭士杰河北工业大学机械工程学院河北省机器人感知与人机融合重点实验室天津300401 智能康复装置与检测技术教育部工程研究中心天津300401

性能优异、持久耐用、制备效率高且成本低的柔性触觉传感器是智能电子皮肤、人机交互、医疗保健的迫切需求。大多数微结构电容式触觉传感器需要洁净室微制造,增加了制作过程的复杂性及制作成本。本文介绍了一种新型且简易有效的方法,通... 详细信息

性能优异、持久耐用、制备效率高且成本低的柔性触觉传感器是智能电子皮肤、人机交互、医疗保健的迫切需求。大多数微结构电容式触觉传感器需要洁净室微制造,增加了制作过程的复杂性及制作成本。本文介绍了一种新型且简易有效的方法,通过简单的工具在聚偏氟乙烯—六氟丙烯共聚物(PVDF-HFP)离子凝胶膜表面大面积制作不同尺寸的微结构,并对其传感特性进行了测试和比较。实验表明:传感器在1.2kPa的压力范围内具有灵敏度高(46.8kPa-1)、检测限低(16Pa)、响应速度快(20ms)等综合性优势;经过6000次高压力循环加载后,不偏离初始性能,表现出极强的鲁棒性以及实用性。本文提出的方法可以显著提高传感器的制备效率和整体性能,同时降低制备过程的资金和时间成本。

关键词：触觉传感器电子皮肤微结构超级电容可穿戴设备

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