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Cryptanalysis and improvement of a quantum secret sharing scheme based on χ-type entangled states 被引量:1
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作者 Zhu zhen-Chao Zhang Yu-Qing Fu An-Min 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期1-5,共5页
In the paper [2010 Chin. Phys. B 19 050306], Yang et al. put forward a novel three-party quantum secret sharing protocol of secure direct communication based on x-type entangled states, they claimed that the scheme is... In the paper [2010 Chin. Phys. B 19 050306], Yang et al. put forward a novel three-party quantum secret sharing protocol of secure direct communication based on x-type entangled states, they claimed that the scheme is secure. However, in this paper, we study the security of the protocol and find that it is insecure. Applying intercept and resend attack, the agent Bob can obtain Alice's secret without the help from the other agent Charlie. In the end, we give our effective modification for its improvement. 展开更多
关键词 quantum secret sharing quantum entanglement bell state nonorthogonal base
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Inference of General Mass Action-Based State Equations for Oscillatory Biochemical Reaction Systems Using <i>k</i>-Step Genetic Programming 被引量:1
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作者 Tatsuya Sekiguchi Hiroyuki Hamada Masahiro Okamoto 《Applied Mathematics》 2019年第8期627-645,共19页
Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP... Systems biology requires the development of algorithms that use omics data to infer interaction networks among biomolecules working within an organism. One major type of evolutionary algorithm, genetic programming (GP), is useful for its high heuristic ability as a search method for obtaining suitable solutions expressed as tree structures. However, because GP determines the values of parameters such as coefficients by random values, it is difficult to apply in the inference of state equations that describe oscillatory biochemical reaction systems with high nonlinearity. Accordingly, in this study, we propose a new GP procedure called “k-step GP” intended for inferring the state equations of oscillatory biochemical reaction systems. The k-step GP procedure consists of two algorithms: 1) Parameter optimization using the modified Powell method—after genetic operations such as crossover and mutation, the values of parameters such as coefficients are optimized by applying the modified Powell method with secondary convergence. 2) GP using divided learning data—to improve the inference efficiency, imposes perturbations through the addition of learning data at various intervals and adaptations to these changes result in state equations with higher fitness. We are confident that k-step GP is an algorithm that is particularly well suited to inferring state equations for oscillatory biochemical reaction systems and contributes to solving inverse problems in systems biology. 展开更多
关键词 SYSTEMS Biology Genetic Programming Inverse Problems OSCILLATORY BIOCHEMICAL Reaction SYSTEMS GMA-based state Equations
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STUDY OF NORTHERN WINTER ATMOSPHERIC ACTIVE CENTERS (AAC) CLIMATE BASE-STATE WITH ITS CLIMATE VARIABILITY AND EFFECTS
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作者 施能 陈辉 夏冬冬 《Journal of Tropical Meteorology》 SCIE 2000年第2期194-201,共8页
The study of low-frequency oscillations is an important part of climate variability research. In view of insufficient efforts spent on multidecadal and ENSO-scale changes of the climate, the present paper undertakes s... The study of low-frequency oscillations is an important part of climate variability research. In view of insufficient efforts spent on multidecadal and ENSO-scale changes of the climate, the present paper undertakes study of > 30 year slowly-varying means, called climate base state (CBS), of northern winter AAC’s in the past 100 years and more, with the CBS variability and its temporal evolution investigated, indicating that Aleutian low and Icelandic low (North Pacific high and North American high) experience maximum (minimum) variation in the CBS. The CBS exhibits two modes for its variation. The positive (negative) phase of mode I presents a weak (strong) NAO (North Atlantic Oscillation), a weaker (stronger) NPO (North Pacific Oscillation), a robust (feeble) Siberian high and a quite weak (vigorous) Aleutian low whilst the positive (negative) phase of mode II reveals a feeble (strong) Aleutian low and a weak (robust) Siberian high. Also, the research shows that the recent CBS of northern circulations is in a remarkably negative phase of mode I and a noticeably positive phase of mode II, viz., in the background of slowly-varying circulations of an exceptionally weak Siberian high, an extremely vigorous Aleutian low and an intense NAO. The background field is likely to persist for a matter of 30 years such that northern winter temperature is expected to be in such a warm situation for a long period to follow. 展开更多
关键词 ATMOSPHERIC active centers CLIMATE base-state CLIMATE variabilit
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Magnetic Field Measurement with Heisenberg Limit Based on Solid Spin NOON State
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作者 周雷鸣 董杨 孙方稳 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期164-168,共5页
The maximum entangled number state (NOON state) can improve the sensitivity of physical quantity measure- ment to the Heisenberg limit 1/N. In this work, the magnetic field measurement based on the individual solid ... The maximum entangled number state (NOON state) can improve the sensitivity of physical quantity measure- ment to the Heisenberg limit 1/N. In this work, the magnetic field measurement based on the individual solid spin NOON state is investigated. Based on the tunable effective coupling coefficient, we propose a generation scheme of the three-spin NOON state, i.e, the Creenberger-Horne-Zeilinger (CHZ) state, and discussed the mea- surement resolution reduction due to decoherence. It is unnecessary to entangle spins as many as possible when decoherence exists. In practice, defect spins in diamond and alp donors with long coherence time can be applied with current techniques in the nano-scaled high resolution magnetic measurement. 展开更多
关键词 Magnetic Field Measurement with Heisenberg Limit based on Solid Spin NOON state
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The singularity in the state-based peridynamic solution of uniaxial tension
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作者 Zaixing Huang 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2018年第5期351-354,363,共5页
We solve the local uniaxial tension of an infinite rod in the framework of non-ordinary state-based peridynamics.The singular solutions of stress and displacement are acquired.When the influencing range of the window ... We solve the local uniaxial tension of an infinite rod in the framework of non-ordinary state-based peridynamics.The singular solutions of stress and displacement are acquired.When the influencing range of the window function approaches zero,these two solutions will return to the solutions of the classical elasticity.The analysis shows that the singularities of the solutions stem from such a feature of the window function that must be represented by a rapidly decreasing function in physics.Contrary to the classical elasticity,the stress solution of peridynamics is smoother than the displacement solution.In addition,a criterion used to select the window function is proposed in this paper. 展开更多
关键词 Peridynmics Non-ordinary state-based PERIDYNAMICS SINGULARITY LOCAL UNIAXIAL tension ANALYTICAL SOLUTION
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Analyzing and Designing Business Processes Management System Based on Transformation of Instantiated Ontology’s State
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作者 YAO Qing WANG Haiyang 《Wuhan University Journal of Natural Sciences》 CAS 2006年第5期1126-1131,共6页
The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find... The paper discusses efforts of finding a simple and transparent method to analyze business processes and developing its management system architecture. By introducing ontology and its state, the approach tried to find a unified representation and a flexible choreography of business processes. The main idea of the paper is the transformation of ontology's states, which are the most important scenarios of enterprises. The business activity composition, that is, case composition based on an AI technique, Case Based Reason (CBR), which is to solve new problems by retrieving solutions to previous problems, and then store the modified solution. The main interest in CBR relies on that it allows a system to avoid past failures and exploit past successes. 展开更多
关键词 ontology business process management (BPM) case based reason(CBR) state transform
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Low Spin State Dinuclear Fe^Ⅲ,Ni^Ⅱand Cu^ⅡComplexes Supported by 1-Amino-2-indanol Schiff Base Derivatives
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作者 崔燕峰 许亚蒙 +5 位作者 孙昊 杨华 张瑾 李亚红 刘玮 董亚萍 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第8期1293-1304,共12页
Four complexes of compositions [Fe2(L^1)2](1), [Ni2(L^1)2](2), [Ni2(L^2)2](3) and [Cu2(L^2)2](4)(H2L^1 = 1-(((2-hydroxy-2,3-dihydro-1 H-inden-1-yl)imino)methyl)naphthalen-2-ol, H2L^2 = 4-((2-h... Four complexes of compositions [Fe2(L^1)2](1), [Ni2(L^1)2](2), [Ni2(L^2)2](3) and [Cu2(L^2)2](4)(H2L^1 = 1-(((2-hydroxy-2,3-dihydro-1 H-inden-1-yl)imino)methyl)naphthalen-2-ol, H2L^2 = 4-((2-hydroxy-2,3-dihydro-1 H-inden-1-yl)imino)pentan-2-one) were synthesized under solvothermal conditions. The structures of 1~4 were characterized by X-ray single-crystal diffraction analysis. The magnetic properties of these four complexes are investigated. The dc magnetic measurements indicate that the metal ions of 1, 2 and 3 are in the low spin state, revealing the strong ligand field character of 1-amino-2-indanol. This work provides an effective approach to coordination complexes possessing low spin state metal centers. 展开更多
关键词 transition metal low spin state Schiff base magnetic property
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Transient state model of actin-based motility
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作者 Li-miao Bai and Yuan Lin~(a)) Department of Mechanical Engineering,The University of Hong Kong,Hong Kong SAR,China 《Theoretical & Applied Mechanics Letters》 CAS 2011年第1期73-76,共4页
We developed a transient model for actin-based motility.Diffusion of actin monomers was included in the formulation and its influence on the speed of actin-driven cargos was examined in detail.Our results clearly demo... We developed a transient model for actin-based motility.Diffusion of actin monomers was included in the formulation and its influence on the speed of actin-driven cargos was examined in detail.Our results clearly demonstrated how actin polymerization accelerates cargos that are initially stationary,as well as how steady-state is eventually reached.We also found that,due to polymerization and diffusion,actin monomer concentration near the load surface can be significantly lower than that in the rest of the comet tail,suggesting that many previous models may not be very accurate. 展开更多
关键词 actin-based motility POLYMERIZATION DIFFUSION transient state
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The Rising,Recession and Revitalization of the Traditional Industrial Base in the Northeastern United States 被引量:1
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作者 姚丽丽 《海外英语》 2012年第23期211-214,共4页
The distribution of American industries has been unbalanced and most of the early industrial regions were centered in northeastern America.The northeastern traditional industrial base once was called"manufacturin... The distribution of American industries has been unbalanced and most of the early industrial regions were centered in northeastern America.The northeastern traditional industrial base once was called"manufacturing belt".Since the 1950s,old industrial bases in the United States have been under recession.The northeastern region was then even called"rust belt".Some issues and measures of policy were set up by the government to adjust and restructure the old industrial bases,and some are useful experience and inspirations for our country,such as setting up special branches and organizations,establishing and implementing strategic planning for the adjustment and restructure of old industrial bases,adjusting the industrial branch and system,emphasizing on environment control and preservation and so on was achieved.Learning the successful experience from America,effective countermeasures and steps must be taken to accelerate the revival of the old industrial base in Northeastern China. 展开更多
关键词 NORTHEASTERN UNITED states traditional industrial
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Optimal Stiffness for Flexible Connectors on A Mobile Offshore Base at Rough Sea States 被引量:1
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作者 WU Lin-jian WANG Yuan-zhan +4 位作者 WANG Yu-chi CHEN Jia-yu LI Yi LI Qing-mei XIE Tao 《China Ocean Engineering》 SCIE EI CSCD 2018年第6期683-695,共13页
This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was us... This paper investigates a simplified method to determine the optimal stiffness of flexible connectors on a mobile offshore base(MOB) during the preliminary design stage. A three-module numerical model of an MOB was used as a case study. Numerous constraint forces and relative displacements for the connectors at rough sea states with different wave angles were utilized to determine the optimized stiffness of the flexible connectors. The range of optimal stiffnesses for the connectors was obtained based on the combination and intersection of the optimized stiffness results, and the implementation steps were elaborated in detail. The percentage reductions of the optimized and optimal stiffness of the flexible connector were determined to quantitatively evaluate the decreases of the constraint force and relative displacement of the connectors compared with those calculated by using the original range of the connector stiffnesses. The results indicate the accuracy and feasibility of this method for determining the optimal stiffness of the flexible connectors and demonstrate the rationality and practicability of the optimal stiffness results. The research ideas, calculation process, and solutions for the optimal stiffness of the flexible connectors of an MOB in this paper can provide valuable technical support for the design of the connectors in similar semisubmersible floating structures. 展开更多
关键词 mobile offshore base(MOB) flexible connectors the optimal stiffness rough sea states
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高容量镁基储氢合金材料研究与应用进展 被引量:2
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作者 邹建新 张嘉祺 +2 位作者 赵颖燕 林羲 丁文江 《金属学报》 北大核心 2025年第3期420-436,共17页
随着近年来氢能产业的迅速发展,镁基固态储氢材料及其储运氢系统得到了全球的广泛关注,出现了许多突破性研究和进展。在新材料体系设计方面,高性能纳米镁基储氢材料和改性镁基铸造合金的研发有效改善了Mg及其氢化物的热力学稳定性和动... 随着近年来氢能产业的迅速发展,镁基固态储氢材料及其储运氢系统得到了全球的广泛关注,出现了许多突破性研究和进展。在新材料体系设计方面,高性能纳米镁基储氢材料和改性镁基铸造合金的研发有效改善了Mg及其氢化物的热力学稳定性和动力学性能,实现了材料在中低温条件下的快速吸脱氢和低成本应用。在系统开发方面,借助先进的模拟方法和设计策略对镁基固态储氢系统的结构与操作参数进行优化,实现了镁基固态储氢系统的有效热管理。在工程应用方面,世界首台吨级镁基固态储运氢车落地,多个镁基固态储运氢示范应用和加氢站也陆续问世。本文从纳米镁基储氢材料、改性镁基储氢合金、镁基储氢系统开发和示范应用4方面讨论了镁基储氢材料的重要研究进展,总结了其在氢能储运领域的相关工程示范及应用,并对未来的研究趋势进行了展望。 展开更多
关键词 氢能 镁基储氢材料 热/动力学性能 数值模拟 镁基固态储运氢系统
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Charge Transfer and Normal State Anomaly in Bi-Based High T_c Superconductors Studied by Positron Annihilation
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作者 Chen Feng Zheng Sheng-nan Zhang Su-qun Gou Zhen-hui Li An-li Zhu Sheng-yun (China Institute of Atomic Energy,P.O.Box 275,Beijing 102413)Liu Zhi-yi Zhao Zhong-xian (Institute of Physics,Chinese Academy of Sciences,Beijing 100080) 《Chinese journal of nuclear physics》 1994年第3期278-282,共5页
The positron annihilation lifetime and Doppler broadened line-shapeparameter have been measured between 77 and 300 K for Bi<sub>1.8</sub>Pb<sub>0.1</sub>Sb<sub>0.1</sub>Sr<sub>... The positron annihilation lifetime and Doppler broadened line-shapeparameter have been measured between 77 and 300 K for Bi<sub>1.8</sub>Pb<sub>0.1</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub>,Bi<sub>1.8</sub>Sb<sub>0.2</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>3</sub>O<sub>x</sub> and Bi<sub>1.7</sub>Pb<sub>0.2</sub>Sb<sub>0.1</sub>Sr<sub>2</sub>Ca<sub>2</sub>Cu<sub>2</sub>O<sub>x</sub>. The charge transfer from Cu-Olayers to Bi-O layers has been observed across T<sub>c</sub>s for all samples.Three samples allshow two normal state anomalies around 160 K and 240 K,respectively.The anomalyaround 160 K is attributed to the structural instability and that around 240 Kpresumably to the displacement phase transition. 展开更多
关键词 Bi-based SUPERCONDUCTORS Charge transfer Normal state ANOMALY Positron annihilation
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基于分解优化并行ESN 的氢燃料电池寿命预测 被引量:1
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作者 华志广 潘诗媛 +2 位作者 赵冬冬 李祥隆 窦满峰 《航空学报》 北大核心 2025年第2期292-306,共15页
针对质子交换膜燃料电池(PEMFC)多时间尺度老化特性导致电压预测精度较低的问题,基于集成经验模态分解(EEMD)与循环系统优化(CSBO)方法,提出了一种并行回声状态网络(PESN)结构,提升了PEMFC的寿命预测精度。采用EEMD对原始电压信号进行... 针对质子交换膜燃料电池(PEMFC)多时间尺度老化特性导致电压预测精度较低的问题,基于集成经验模态分解(EEMD)与循环系统优化(CSBO)方法,提出了一种并行回声状态网络(PESN)结构,提升了PEMFC的寿命预测精度。采用EEMD对原始电压信号进行模态分解,将不同时刻的历史数据及分解得到的不同频率信号作为ESN不同子蓄水池的并行输入,构建一种按权重分配叠加输出的并行ESN结构,利用CSBO优化并行ESN结构的相关参数,基于优化后的EPESN模型实现PEMFC未来数百小时输出电压的预测。在稳态和准动态70%的数据训练集下,EPESN比ESN的均方根误差分别降低了34.25%和47.41%。在动态1训练时长为300 h时,EPESN比ESN的均方根误差降低了15.30%。结果表明:EPESN结构能够提高PEMFC寿命的预测精度。 展开更多
关键词 质子交换膜燃料电池 寿命预测 经验模态分解 循环系统优化 回声状态网络
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污染场地修复义务的继受
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作者 刘静 《中国土地科学》 北大核心 2025年第4期49-57,共9页
研究目的:研究污染场地修复义务的继受问题,以期定分止争,对未来的土地开发建设活动提供指引。研究方法:规范分析法、比较分析法和案例分析法。研究结果:(1)我国立法未能全面回答责任主体变更和土地权利转移时,修复义务人的认定这一难题... 研究目的:研究污染场地修复义务的继受问题,以期定分止争,对未来的土地开发建设活动提供指引。研究方法:规范分析法、比较分析法和案例分析法。研究结果:(1)我国立法未能全面回答责任主体变更和土地权利转移时,修复义务人的认定这一难题。(2)在主体变更情形下,应由继受者承担修复的行为义务和财务负担,企业组织形态或出资人的变动不影响修复义务的承担。(3)在个别继受方面,对于发生在《土壤污染防治法》生效后的土地使用权转让或收购,受让人同时承担修复的行为义务和财务负担;此前的土地使用权转移,受让人承担默示的修复义务后,可向土壤污染责任人或土壤污染防治基金求偿;(4)在政府征收土地或收回土地使用权情形下,不论其发生时间,都应由政府承担修复义务和费用。研究结论:应综合考虑修复的有效性、合比例性,以及对潜在义务主体的行为激励效果,在类型化的基础上完善土壤污染修复义务人的认定规则。 展开更多
关键词 污染场地修复 行为责任 状态责任 概括继受 个别继受
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基于状态势博弈的微电网能量管理优化算法研究
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作者 曾君 谭豪杰 +3 位作者 刘俊峰 曾婧瑶 陈云 朱威 《电力系统保护与控制》 北大核心 2025年第5期24-34,共11页
有效的能量管理系统是微电网安全、经济运行的关键技术。综合考虑可再生能源出力和需求侧负荷的灵活性,提出一种基于状态势博弈理论的微电网能量管理方法。首先,充分考虑用户侧灵活性资源,将用户负荷分为基础负荷和各柔性负荷,并对微电... 有效的能量管理系统是微电网安全、经济运行的关键技术。综合考虑可再生能源出力和需求侧负荷的灵活性,提出一种基于状态势博弈理论的微电网能量管理方法。首先,充分考虑用户侧灵活性资源,将用户负荷分为基础负荷和各柔性负荷,并对微电网内各主体进行建模。然后,以微电网内各元件单元作为独立的决策主体,建立状态势博弈模型。最后,在博弈外层嵌套遗传算法,实现可平移负荷和可转移负荷的周期性约束。仿真结果表明:在保证各主体自主性的前提上,所提方法在很大程度上提高了可再生能源的消纳水平;一定程度上提高了用户用电的经济性,实现了柔性负荷虚拟充放电的功能。与完全势博弈和非博弈方法相比,所提方法更能体现各主体的平等地位,同时通过极小化各主体间的通信量实现了各主体之间的隐私保护。 展开更多
关键词 微电网 状态势博弈 能量管理 柔性负荷 纳什均衡
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Research on evaluation model of technology innovation ability of state-owned enterprises in northeast industry base
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作者 CHEN Hongguang QI Guoyou ZHANG Ning 《Journal of Northeast Agricultural University(English Edition)》 CAS 2007年第2期184-187,共4页
The paper viewed the current problem that state-owned enterprises in northeast industry base hadn't technologies of their own intellectual property right, whose sources mainly depended on imitation and introduction f... The paper viewed the current problem that state-owned enterprises in northeast industry base hadn't technologies of their own intellectual property right, whose sources mainly depended on imitation and introduction from abroad. Operational evaluation method and index criteria system of enterprises technology innovation ability were put forward in this paper, different enterprises may revise the model according to their actual situations to evaluate the enterprise technological innovation ability scientifically and quickly. The findings will be helpful to correlative departments to formulate the related policies and also has important theoretical and practical value in technological innovation project of enterprise. 展开更多
关键词 state-owned enterprises in northeast industry base technology innovation ability appraised criteria system
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基于自适应特征增强和融合的舰载机着舰拉制状态识别 被引量:1
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作者 王可 刘奕阳 +3 位作者 杨杰 鲁爱国 李哲 徐明亮 《上海交通大学学报》 北大核心 2025年第2期274-282,共9页
拉制状态识别能辅助着舰信号官及时准确地形成后续指挥决策,是舰载机着舰引导的重要环节.提出一种基于自适应特征增强和融合的拉制状态识别方法,包含基于注意力机制的特征增强模块,通过分割特征图、串联空间域和通道域增强视觉表征能力... 拉制状态识别能辅助着舰信号官及时准确地形成后续指挥决策,是舰载机着舰引导的重要环节.提出一种基于自适应特征增强和融合的拉制状态识别方法,包含基于注意力机制的特征增强模块,通过分割特征图、串联空间域和通道域增强视觉表征能力;利用多尺度特征融合模块,将高分辨率浅层特征与语义信息丰富的深层特征进行融合,充分利用上下文语义信息.基于所提方法,设计基于可穿戴增强现实设备的着舰拉制状态识别原型系统;构建着舰作业虚实融合数据集以评估方法性能.结果表明,所提算法综合性能优于基线算法,能满足拉制状态识别的应用需求. 展开更多
关键词 舰载机 阻拦着舰 特征融合 注意力机制 状态识别
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文明互鉴论视野中的老舍及其文化价值选择的两端性
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作者 耿传明 王艺璇 《求是学刊》 北大核心 2025年第2期153-168,共16页
老舍的文化价值选择突出表现为在传统与现代、东方与西方之间的斟酌与磨合:他一方面从动机和目标上认同五四,但又不满于五四启蒙者居高临下的精英主义;他钦羡将个人完全依附于国家的近代西方人的国家崇拜,但也深知其偏狭和不足;他以深... 老舍的文化价值选择突出表现为在传统与现代、东方与西方之间的斟酌与磨合:他一方面从动机和目标上认同五四,但又不满于五四启蒙者居高临下的精英主义;他钦羡将个人完全依附于国家的近代西方人的国家崇拜,但也深知其偏狭和不足;他以深厚的市民生活经验和与生俱来的幽默感见长,但他同时又是中国市民生活自觉的批判者和严峻的审视者。他对固有传统充满温情和眷恋,但又深知其所爱者恰恰可能成为中国人通往现代生存的最大阻碍;他的国民性批判具有鲜明的理性主义的现代性诉求,但其个人的灵魂深处仍基本表现为一种温良恭俭、行己有耻的传统底色。老舍的文化价值选择具有超越时代信条的自主性和切己性,他对现代文化的探索为我们走出文明一元论的、非此即彼的、二元对立的文明观提供了范例,为我们认识现代中国人徘徊于中西古今之间的深邃而又复杂的两端性考量提供了见证。 展开更多
关键词 老舍 国家本位启蒙 两端性 文明互鉴论 温和与刚毅
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爆炸载荷下钢筋混凝土板近场动力学仿真研究
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作者 吴凡 段庆林 《计算机仿真》 2025年第4期541-544,556,共5页
基于常规态型近场动力学模型,对钢筋混凝土板进行了建模,并进行了数值仿真。提出钢筋和混凝土两种材料的模拟方案,使其能够在统一框架下进行数值计算。进一步地,建立了高应变率下的简化断裂准则,实现了钢筋混凝土板在爆炸载荷下多裂纹... 基于常规态型近场动力学模型,对钢筋混凝土板进行了建模,并进行了数值仿真。提出钢筋和混凝土两种材料的模拟方案,使其能够在统一框架下进行数值计算。进一步地,建立了高应变率下的简化断裂准则,实现了钢筋混凝土板在爆炸载荷下多裂纹破坏的数值仿真。与实验结果对比,数值结果能很好地捕捉到实验结果中展现出的环向裂纹和径向裂纹等多种典型的裂纹特征,从而验证了所提出的基于常规态型近场动力学理论的钢筋混凝土模型的有效性。 展开更多
关键词 近场动力学 常规态型 钢筋混凝土 爆炸载荷 多裂纹
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中国式养老的历史变迁与现代重构——基于“家国一体”视角的考察 被引量:8
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作者 林闽钢 《浙江社会科学》 北大核心 2025年第1期92-99,158,共9页
中国传统养老模式具有家国共责的双层构造及社会伦理支撑。社会主义计划经济时期开启了以单位为载体的社会养老方式的结构化,社会主义市场经济时期以社区为载体的养老方式再结构化,实现了由传统养老模式向现代社会养老服务体系的转化,... 中国传统养老模式具有家国共责的双层构造及社会伦理支撑。社会主义计划经济时期开启了以单位为载体的社会养老方式的结构化,社会主义市场经济时期以社区为载体的养老方式再结构化,实现了由传统养老模式向现代社会养老服务体系的转化,其实质是中国“家国一体”养老的现代延展。当前,城市社区嵌入式养老和农村社区链式养老成为社会服务体系融合发展的新趋向。为此,本文从“家国一体”的视角出发提出新时代推动中国式养老发展的方略,即倡导新时代老龄文明,构建养老服务共同体;从“居家养老社区化”和“机构养老社区化”两条发展路径,促进养老服务高质量发展。 展开更多
关键词 中国式养老 社会养老服务体系 家国一体 居家养老社区化 机构养老 社区化
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