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气囊着陆缓冲过程仿真分析

载人航天 2018年第4期24卷 529-535页

作者：卫剑征王滢甄铎谭惠丰杨知寒哈尔滨工业大学复合材料与结构研究所哈尔滨150080

针对气囊着陆缓冲与反弹问题,以对称的胶囊状双气囊缓冲系统为研究对象,提出了气囊的等效弹簧刚度和阻尼模型,讨论了着陆速度与气囊等效阻尼的变化关系。建立了双缓冲气囊的有限元模型,基于显式计算方法对双气囊有无排气孔的着陆缓冲过... 详细信息

针对气囊着陆缓冲与反弹问题,以对称的胶囊状双气囊缓冲系统为研究对象,提出了气囊的等效弹簧刚度和阻尼模型,讨论了着陆速度与气囊等效阻尼的变化关系。建立了双缓冲气囊的有限元模型,基于显式计算方法对双气囊有无排气孔的着陆缓冲过程进行了仿真,表明有排气孔气囊能实现软着陆。建立了有排气孔的芳纶织物双气囊缓冲试验系统,通过电磁快速释放装置完成了双气囊被动式排气孔的测试。结果表明,被动式排气孔的胶囊状气囊能有效起到缓冲作用,无侧翻和明显反弹,并验证了设计方法的正确性。

关键词：陆缓冲气囊排气孔着陆反弹

The reformation of catalyst:From a trial-and-error synthesis to rational design

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Nano Research 2024年第4期17卷 3261-3301页

作者： Ligang wang Jiabin Wu Shunwu wang Huan Liu Yao wang Dingsheng wang Department of Chemistry Tsinghua UniversityBeijing 100084China

The appropriate catalysts can accelerate the reaction rate and effectively boost the efficient conversion of various molecules,which is of great importance in the study of chemistry,chemical industry,energy,materials and environmental ***,efficient,environmentally friendly,and easy to operate synthesis methods have been used to prepare various types of *** previous studies have reported the synthesis and characterization of the aforementioned catalysts,more still remain in trial and error methods,without in-depth consideration and improvement of traditional synthesis ***,we comprehensively summarize and compare the preparation methods of the trial-and-error synthesis strategy,structure–activity relationships and density functional theory(DFT)guided catalysts rational design for nanomaterials and atomically dispersed *** also discuss in detail the utilization of the nanomaterials and single atom catalysts for converting small molecules(H_(2)O,O_(2),CO_(2),N_(2),etc.)into value-added products driven by electrocatalysis,photocatalysis,and ***,the challenges and outlooks of mass preparation and production of efficient and green catalysts through conventional trial and error synthesis and DFT theory are featured in accordance with its current development.

关键词： trial-and-error synthesis structure–activity relationships density functional theory(DFT)guidance nanomaterials atomically dispersed catalysts

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网络法治下《网络安全法》的法律实践研究

现代农业研究 2019年第7期25卷 119-120页

作者：王健铮李宗建黑龙江大学

自《网络安全法》实施以来,出现了执法部门权职划分未清、配套条例未健全等问题有待解决。对它的执法问题的分析,有利于我国完善我国相关法律体系。

关键词：网络安全法实践问题法律研究

Numerical Analysis of PRISM-PY Calculations for Hard-and Soft-Core Generic Polymer Models

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Chinese Journal of Polymer Science 2024年第4期42卷 532-543页

作者： Qiang wang Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be classified, according to whether or not the 3D integral of the latter diverges, into hard- and soft-core models. Taking homogeneous systems of compressible homopolymer melts (or equivalently homopolymer solutions in an implicit, good solvent) in the continuum as an example, we recently compared the correlation effects on the structural and thermodynamic properties of the hard- and soft-core models given by the polymer reference interaction site model (PRISM) theory with the Percus-Yevick (PY) closure (Polymers 2023, 15, 1180). Here we analyzed in detail the numerical errors and behavior of the interchain pair correlation functions (PCFs) given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed. Our numerical approach has the least number of independent variables to be iteratively solved, analytically treats the discontinuities caused by the non-bonded pair potential (such as that of the hard spheres) and takes only the inverse Fourier transform of the interchain indirect PCF between polymer segments (which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs), and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106. To capture the correlation-hole effect, the real-space cut-off in the PRISM calculations should be proportional to the square root of N.

关键词： Generic polymer models Soft potentials Polymer reference interaction site model theory

Linear-Quadratic Pareto Cooperative Game for Mean-Field Backward Stochastic System

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Journal of Systems Science & Complexity 2024年第3期37卷 947-964页

作者： wang Yu School of Control Science and Engineering Shandong UniversityJinan 250061China

This paper focuses on a Pareto cooperative differential game with a linear mean-field backward stochastic system and a quadratic form cost functional. Based on a weighted sum optimality method, the Pareto game is equivalently converted to an optimal control problem. In the first place,the feedback form of Pareto optimal strategy is derived by virtue of decoupling technology, which is represented by four Riccati equations, a mean-field forward stochastic differential equation(MF-FSDE),and a mean-field backward stochastic differential equation(MF-BSDE). In addition, the corresponding Pareto optimal solution is further obtained. Finally, the author solves a problem in mathematical finance to illustrate the application of the theoretical results.

关键词： Backward stochastic differential equation linear-quadratic control mean-field Pareto optimality

1例基于免疫联合瑞戈非尼治疗晚期升结肠癌肝转移病例的分享

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肿瘤综合治疗电子杂志 2022年第4期8卷 114-118页

作者：王建正陈小兵郑州大学附属肿瘤医院河南省肿瘤医院消化内科郑州450008

1 病例资料患者,女,56岁,初始因腹胀伴恶心呕吐、反酸、乏力,于2018年11月15日在当地县人民医院行肠镜检查提示:升结肠近肝曲可见该部肠腔四壁高低不平菜花样新生物,质硬脆,触之易出血,取病理示结肠腺癌。CT检查示多发肝转移,临床分期:c... 详细信息

1 病例资料患者,女,56岁,初始因腹胀伴恶心呕吐、反酸、乏力,于2018年11月15日在当地县人民医院行肠镜检查提示:升结肠近肝曲可见该部肠腔四壁高低不平菜花样新生物,质硬脆,触之易出血,取病理示结肠腺癌。CT检查示多发肝转移,临床分期:cTNMⅣ期。既往史:2019年行左侧乳腺癌根治术,具体病理类型不详,术后行4个周期辅助化疗。治疗方案:2018年12月于南阳医学高等专科学校第一附属医院行mFOLFOX6方案化疗3个周期。

关键词：乳腺癌根治术菜花样结肠腺癌结肠癌肝转移辅助化疗肠镜检查病例资料肝曲

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高功率微波对北斗系统接收机影响分析

舰船电子工程 2019年第10期39卷 27-29页

作者：王建争彭少磊 91404部队42分队

针对高功率微波对北斗系统接收机的威胁,介绍了高功率微波对北斗系统接收机的损伤效应和耦合效应,分析了高功率微波的作用对象,从系统、器件以及材料三个层级给出了接收机的防护措施。

关键词：高功率微波北斗系统接收机防护措施

A multi-source information fusion layer counting method for penetration fuze based on TCN-LSTM

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Defence Technology（防务技术） 2024年第3期33卷 463-474页

作者： Yili wang Changsheng Li Xiaofeng wang Nanjing University of Science and Technology Nanjing 210094JiangsuChina State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

When employing penetration ammunition to strike multi-story buildings,the detection methods using acceleration sensors suffer from signal aliasing,while magnetic detection methods are susceptible to interference from ferromagnetic materials,thereby posing challenges in accurately determining the number of *** address this issue,this research proposes a layer counting method for penetration fuze that incorporates multi-source information fusion,utilizing both the temporal convolutional network(TCN)and the long short-term memory(LSTM)recurrent *** leveraging the strengths of these two network structures,the method extracts temporal and high-dimensional features from the multi-source physical field during the penetration process,establishing a relationship between the multi-source physical field and the distance between the fuze and the target plate.A simulation model is developed to simulate the overload and magnetic field of a projectile penetrating multiple layers of target plates,capturing the multi-source physical field signals and their patterns during the penetration *** analysis reveals that the proposed multi-source fusion layer counting method reduces errors by 60% and 50% compared to single overload layer counting and single magnetic anomaly signal layer counting,*** model's predictive performance is evaluated under various operating conditions,including different ratios of added noise to random sample positions,penetration speeds,and spacing between target *** maximum errors in fuze penetration time predicted by the three modes are 0.08 ms,0.12 ms,and 0.16 ms,respectively,confirming the robustness of the proposed ***,the model's predictions indicate that the fitting degree for large interlayer spacings is superior to that for small interlayer spacings due to the influence of stress waves.

关键词： Penetration fuze Temporal convolutional network(TCN) Long short-term memory(LSTM) Layer counting Multi-source fusion

Framework for Preventive Control of Power Systems to Defend Against Extreme Events

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 856-870页

作者： Yuwei Xiang Tong wang Zengping wang State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China

Enhancing power system resilience against extreme events is becoming increasingly critical. This paper discusses a unified framework for preventive control of power systems to enhance system resilience, which includes three parts: resilience assessment, resilience grading, and resilience enhancement. First, the resilience assessment contains facility-level and system-level resilience assessment. The concept of fragility curve is used in the facility-level resilience assessment. Various resilience indices are developed in system-level resilience assessment to roundly depict the impacts of extreme events on power systems and determine the system resilience. On this basis, the resilience is divided into different levels by resilience grading strategy, which can efficiently quantify the severity of the impact of extreme events and provide decision-making for the resilience enhancement strategies. Then, control strategies for enhancing power system resilience are also divided according to different resilience levels. A controlled islanding based preventive control is proposed to enhance system resilience, which aims to strengthen the first defensive line of power systems to deal with extreme events. Finally, taking the typhoon disaster in extreme events as an example, two tests carried out with two typhoons demonstrate the efficiency of the proposed method.

关键词： Controlled islanding extreme events power system resilience preventive control