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Understanding Chemical Reactivity in Extended Systems:Exploring Models of Chemical Softness in Carbon Nanotubes
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作者 CáRDENAS Carlos MUNOZ Macarena +3 位作者 CONTRERAS Julia AYERS Paul W. GóMEZ Tatiana FUENTEALBA Patricio 《物理化学学报》 SCIE CAS CSCD 北大核心 2018年第6期631-638,共8页
Chemical reactivity towards electron transfer is captured by the Fukui function.However,this is not well defined when the system or its ions have degenerate or pseudo-degenerate ground states.In such a case,the first-... Chemical reactivity towards electron transfer is captured by the Fukui function.However,this is not well defined when the system or its ions have degenerate or pseudo-degenerate ground states.In such a case,the first-order chemical response is not independent of the perturbation and the correct response has to be computed using the mathematical formalism of perturbation theory for degenerate states.Spatialpseudo-degeneracy is ubiquitous in nanostructures with high symmetry and totally extended systems.Given the size of these systems,using degenerate-state perturbation theory is impractical because it requires the calculation of many excited states.Here we present an alternative to compute the chemical response of extended systems using models of local softness in terms of the local density of states.The local softness is approximately equal to the density of states at the Fermi level.However,such approximation leaves out the contribution of inner states.In order to include and weight the contribution of the states around the Fermi level,a model inspired by the long-range behavior of the local softness is presented.Single wall capped carbon nanotubes(SWCCNT)illustrate the limitation of the frontier orbital theory in extended systems.Thus,we have used a C360 SWCCNT to test the proposed model and how it compares with available models based on the local density of states.Interestingly,a simple Hückel approximation captures the main features of chemical response of these systems.Our results suggest that density-of-states models of the softness along simple tight binding Hamiltonians could be used to explore the chemical reactivity of more complex system,such a surfaces and nanoparticles. 展开更多
关键词 Local softness Fukui function REACTIVITY Carbon nanotubes Density of states
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Soft-DDPG算法驱动的综合能源系统优化调度方法
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作者 韩光洁 邹昕莹 +1 位作者 张帆 徐政伟 《小型微型计算机系统》 北大核心 2025年第9期2258-2265,共8页
近年来,综合能源系统作为一种以多种能源形态和设备相互交互的能源系统方案得到了广泛应用和研究.然而,在面对动态复杂的多能源系统时,传统的优化调度方法往往无法满足其实时性和精准度需求.因此,本文设计了一种软深度确定性策略梯度(So... 近年来,综合能源系统作为一种以多种能源形态和设备相互交互的能源系统方案得到了广泛应用和研究.然而,在面对动态复杂的多能源系统时,传统的优化调度方法往往无法满足其实时性和精准度需求.因此,本文设计了一种软深度确定性策略梯度(Soft Deep Deterministic Policy Gradient,Soft-DDPG)算法驱动的综合能源系统优化调度方法,以最小化调度周期内系统总运行成本为目标,建立设备运行综合能效评估模型,再采用Soft-DDPG算法对每个能源设备的能效调度动作进行优化控制.Soft-DDPG算法将softmax算子引入到动作值函数的计算中,有效降低了Q值高估问题.与此同时,该算法在动作选择策略中加入了随机噪声,提高了算法的学习效率.实验结果显示,本文所提出的方法解决了综合能源系统能效调度实时性差、精准度低的瓶颈问题,实现了系统的高效灵活调度,降低了系统的总运行成本. 展开更多
关键词 深度强化学习 优化调度 综合能源系统 Soft DDPG
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基于Soft均值滤波的鲁棒主成分分析算法
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作者 吴沁停 王新景 +3 位作者 潘金艳 张海峰 邵桂芳 高云龙 《光学精密工程》 北大核心 2025年第6期961-978,共18页
降维对于数据的可视化和预处理具有重要意义,主成分分析作为最常用的无监督降维算法之一,在实际应用中面临着对噪声和离群点敏感的问题。为了解决这个问题,研究者们提出了多种鲁棒主成分分析算法,通过减小整体样本的重构误差来减小离群... 降维对于数据的可视化和预处理具有重要意义,主成分分析作为最常用的无监督降维算法之一,在实际应用中面临着对噪声和离群点敏感的问题。为了解决这个问题,研究者们提出了多种鲁棒主成分分析算法,通过减小整体样本的重构误差来减小离群点的影响。然而,这些算法忽略了数据的固有局部结构,导致数据的本质结构信息丢失,从而影响了对噪声和离群点的准确辨识和移除,进而影响了后续算法的性能。因此,该文提出了基于Soft均值滤波的鲁棒主成分分析(Robust Principal Component Analysis Based on Soft Mean Filtering,RPCA-SMF)算法。RPCA-SMF采用Soft均值滤波的思想,通过两步走的形式,不仅在模型学习前对噪声处理,同时在模型学习后也引入了噪声处理机制。具体而言,RPCA-SMF算法首先引入了均值滤波的相关思想,通过对比样本与其局部近邻这两者和局部均值的偏差对样本进行Soft加权,从而对噪声进行判定。随后,通过第一步获取的关于噪声的“判别知识”处理噪声信息。由于均值滤波能有效保留数据的整体轮廓信息,因此对于被识别为噪声的样本,RPCA-SMF算法强调保留其低频整体轮廓信息,而非高频的噪声信息。这样能够有效地保留数据中的有用信息,提高对数据整体结构特征的保留能力,使得算法具有较强的鲁棒性和较好的泛化性。 展开更多
关键词 降维 无监督特征提取 主成分分析 Soft均值滤波 鲁棒性
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Conventional carbon anodes for potassium-ion batteries:Progress,challenges and prospects
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作者 CAO Bin CUI Zheng +2 位作者 LIU Huan ZHANG Shuang-yin XU Bin 《新型炭材料(中英文)》 北大核心 2025年第4期717-737,共21页
As an emerging electrochemical energy storage technology,potassium-ion batteries(PIBs),which are considered a“beyond Li-ion”battery system,have attracted tremendous attention due to their potential for providing a h... As an emerging electrochemical energy storage technology,potassium-ion batteries(PIBs),which are considered a“beyond Li-ion”battery system,have attracted tremendous attention due to their potential for providing a high energy density,and having abundant resource,and a low cost.However,their commercialization is hindered by the lack of practical anode materials.Among various reported anodes,conventional carbon materials,including graphite,soft carbon,and hard carbon,have emerged as promising candidates because of their abundance,low cost,high conductivity,and tunable structures.However,these materials have problems such as a low initial Coulombic efficiency,significant volume expansion,and unsatisfactory cyclability and rate performance.Various strategies to solve these have been explored,including optimizing the interlayer spacing,structural design,surface coating,constructing a multifunctional framework,and forming composites.This review provides a comprehensive overview of the recent progress in conventional carbon anodes,highlighting structural design strategies,mechanisms for improving the electrochemical performance,and underscores the critical role of these materials in promoting the practical application of PIBs. 展开更多
关键词 Potassium-ion batteries Carbon anode GRAPHITE Soft carbon Hard carbon
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AXPs/SGRs:strange stars with crusts?
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作者 Guojun Qiao Lunhua Shang +5 位作者 Renxin Xu Kejia Lee Yongquan Xue Qijun Zhi Jiguang Lu Juntao Bai 《中国科学技术大学学报》 北大核心 2025年第4期2-12,1,I0001,共13页
The emission of anomalous X-ray pulsars(AXPs)and soft gamma-ray repeaters(SGRs)is believed to be powered by the dissipation of their strong magnetic fields,which coined the name“magnetar”.By combining timing and ene... The emission of anomalous X-ray pulsars(AXPs)and soft gamma-ray repeaters(SGRs)is believed to be powered by the dissipation of their strong magnetic fields,which coined the name“magnetar”.By combining timing and energy observational results,the magnetar model can be easily appreciated.From a timing perspective,the magnetic field strengths of AXPs and SGRs,which are calculated under the assumption of dipole radiation,are extremely strong.From an energy perspective,the X-ray/soft gamma-ray luminosities of AXPs and SGRs are larger than their rotational energy loss rates(i.e.,L_(x>E_(rot)).It is thus reasonable to assume that the high-energy radiation comes from magnetic energy decay,and the magnetar model has been extensively discussed(or accepted).However,we argue that:(ⅰ)Calculating magnetic fields by assuming that rotational energy loss is dominated by dipole radiation(i.e.,E_(rot)■E_(μ))may be controversial,and we suggest that the energies carried by outflowing particles should also be considered.(ⅱ)The fact that X-ray luminosity is greater than the rotational energy loss rate does not necessarily mean that the emission energy comes from the magnetic field decaying,which requires further observational testing.Furthermore,some observational facts conflict with the“magnetar”model,such as observations of anti-magnetars,high magnetic field pulsars,and radio and X-ray observations of AXPs/SGRs.Therefore,we propose a crusted strange star model as an alternative,which can explain many more observational facts of AXPs/SGRs. 展开更多
关键词 PULSARS anomalous X-ray pulsars soft gamma-ray repeaters MAGNETARS strange stars
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Simultaneous influences of nanomaterial and fiber reinforcement on enhancing the mechanical performance of geopolymer stabilized soft clayey soils
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作者 KHOSRAVI Hassan GOODARZI Amir Reza LAJEVARDI Seyed Hamid 《Journal of Central South University》 2025年第2期597-623,共27页
This study was designed to enhance the soft clayey soil treatment effects using an innovative mechanochemically activated geopolymer(GP)through the optimized inclusion of nano-metakaolin(NM)and polypropylene fiber.The... This study was designed to enhance the soft clayey soil treatment effects using an innovative mechanochemically activated geopolymer(GP)through the optimized inclusion of nano-metakaolin(NM)and polypropylene fiber.The study also investigated the possible improvements in the binding ability of GP stabilization under different curing regimes.To this end,binders including lime alone,LG(slag-based geopolymer),LGNM(nano-modified LG with NM)and LGNMF(LGNM/fiber)mixture were separately added to soft soil samples.The fabricated composites were then subjected to a set of macro and micro level tests.The results indicated that,adding LG binary with a 20%NM replacement can lead to a significant increase(by nearly 21 times)in soil strength and a remarkable decline(about 70%)in the compression index.In fact,NM can play a great role in accelerating the rate of hydration reactions and forming a densely packed fabric,which staggeringly improve the soil hydromechanical attributes.It was also observed that raising the curing temperature will effectively augment the polymerization kinetics,leading to a substantial increase(~2 times)in the soil solidification process.However,the stabilized composites containing NM may reveal a brittle nature under more intense stress.Such a potential drawback seems to be resolved by the integration of fibers within the matrix.LGNM combined with fiber would boost(≥10 times)the energy absorption capacity of the soil,notably enhancing its residual strength.Overall,LGNMF may not only feature a broader range of benefits(inc.economic,technical,environmental)compared to traditional binders but also promote the ductility of the GP materials. 展开更多
关键词 soft clayey soil LIME slag-based geopolymer nano-metakaolin(NM) fiber enhanced nanomodification
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Exploring the effects of angle of incidence on stabbing resistance in advanced protective textiles:Novel experimental framework and analysis
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作者 Mulat Alubel Abtew François Boussu Irina Cristian 《Defence Technology(防务技术)》 2025年第2期67-82,共16页
Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and... Despite numerous research investigations to understand the influences of various structural parameters,to the authors'knowledge,no research has been the effect of different angles of incidence on stab response and performance of different types of protective textiles.Three distinct structures of 3D woven textiles and 2D plain weave fabric made with similar high-performance fiber and areal density were designed and manufactured to be tested.Two samples,one composed of a single and the other of 4-panel layers,from each fabric type structure,were prepared,and tested against stabbing at[0○],[22.5○],and[45○]angle of incidence.A new stabbing experimental setup that entertained testing of the specimens at various angles of incidence was engineered and utilized.The stabbing bench is also equipped with magnetic sensors and a UK Home Office Scientific Development Branch(HOSDB)/P1/B sharpness engineered knives to measure the impact velocity and exerted impact energy respectively.A silicon compound was utilized to imprint the Back Face Signature(BFS)on the backing material after every specimen test.Each silicon print was then scanned,digitized,and precisely measured to evaluate the stab response and performance of the specimen based on different performance variables,including Depth of Trauma(DOT),Depth of Penetration(DOP),and Length of Penetration(LOP).Besides,the post-impact surface failure modes of the fabrics were also measured using Image software and analyzed at the microscale level.The results show stab angle of incidence greatly influences the stab response and performance of protective textiles.The outcome of the study could provide not only valuable insights into understanding the stab response and capabilities of protective textiles under different angle of incidence,but also provide valuable information for protective textile manufacturer,armor developer and stab testing and standardizing organizations to consider the angle of incidence while developing,testing,optimizing,and using protective textiles in various applications. 展开更多
关键词 2D/3D woven fabrics Impact protective fabric Drop tower perforation test Stab resistance testing protocol Angle of incidence Multi-layer panels Soft body armor Impact surface damage
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基于知识辅助深度强化学习的巡飞弹组动态突防决策 被引量:1
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作者 孙浩 黎海青 +2 位作者 梁彦 马超雄 吴翰 《兵工学报》 EI CAS CSCD 北大核心 2024年第9期3161-3176,共16页
巡飞弹组(Loitering Munition Group,LMG)突防控制决策是提高巡飞弹群组作战自主性与智能性的关键。针对存在截击拦截器和临机防空火力区的动态环境中弹组突防机动指令在线生成困难的问题,提出一种基于知识辅助强化学习方法的LMG突防控... 巡飞弹组(Loitering Munition Group,LMG)突防控制决策是提高巡飞弹群组作战自主性与智能性的关键。针对存在截击拦截器和临机防空火力区的动态环境中弹组突防机动指令在线生成困难的问题,提出一种基于知识辅助强化学习方法的LMG突防控制决策算法。结合领域知识、规则知识改进状态空间和回报函数设计提高算法泛化能力与训练收敛速度。构建基于软动作-评价方法的LMG突防控制决策框架,以提高算法探索效率。利用专家经验和模仿学习方法改善多弹多威胁带来的解空间狭窄、算法初始高效训练经验匮乏的问题。实验结果表明,新算法能够在动态环境中实时生成有效的突防机动指令,相较于对比方法效果更好,验证了算法的有效性。 展开更多
关键词 巡飞弹组 知识辅助深度强化学习 Soft Actor-Critic算法 动态环境突防 控制决策
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基于改进的Yolov5的无人机图像小目标检测 被引量:9
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作者 何宇豪 易明发 +1 位作者 周先存 王冠凌 《智能系统学报》 CSCD 北大核心 2024年第3期635-645,共11页
为了解决无人机航拍图像小目标检测算法检测速度与精度无法兼顾的问题,在Yolov5的基础上,提出了针对于无人机图像小目标检测的Yolov5_GBCS算法。在新的算法中,添加一个额外的检测头,以便增强对小目标的特征融合效果;在主干网络中分别采... 为了解决无人机航拍图像小目标检测算法检测速度与精度无法兼顾的问题,在Yolov5的基础上,提出了针对于无人机图像小目标检测的Yolov5_GBCS算法。在新的算法中,添加一个额外的检测头,以便增强对小目标的特征融合效果;在主干网络中分别采用GhostConv卷积模块、GhostBottleneckC3模块替换部分Conv模块和C3模块用以提取丰富特征和冗余特征以提高模型效率;引入加权双向特征金字塔网络(bidirectional feature pyramid network,BiFPN)结构,用以提高对小目标的检测精度;在主干网络和颈部网络中引入轻量化的卷积块注意力模块(convolutional block attention module,CBAM),关注重要特征并抑制不必要的特征,增强小目标特征表达能力;使用Soft-NMS算法来替换NMS,因此降低了小目标在密集场景下的漏检率。通过在VisDrone2019数据集上的实验结果表明,集成了所有改进的方法后的Yolov5_GBCS算法,不仅提高了检测精度,而且有效地提高了检测速度,模型的mAP从38.5%提高到43.2%,检测速度也从53 f/s提高到59 f/s。Yolov5_GBCS算法可以有效地实现无人机航拍图像中小目标识别。 展开更多
关键词 图像处理 GhostConv卷积模块 双向特征金字塔网络 卷积块注意力模块 Soft双向特征金字塔网络 轻量化模型 小目标检测 VisDrone数据集
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Case study on the mechanics of NPR anchor cable compensation for large deformation tunnel in soft rock in the Transverse Mountain area,China 被引量:1
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作者 LI Yong ZHENG Jing +3 位作者 HUO Shu-sen WANG Feng-nian HE Man-chao TAO Zhi-gang 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第6期2054-2069,共16页
A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced duri... A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel,located in the western Transverse Mountain area.A large deformation problem was experienced during the tunnel construction.To mitigate this problem,a support system was designed incorporating negative Poisson ratio(NPR)anchor cables with negative Poisson ratio effect.Physical model experiments,field experiments,and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor cables.The large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress,a high degree of joint fracture development,and a high degree of surrounding rock fragmentation.A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force(approximately 350 kN)for the surrounding rock inside the tunnel.Comparing the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system,combining cables of 6.3 m and 10.3 m in length,effectively prevented convergence of surrounding rock deformation,and the integrated settlement convergence value remained below 300 mm.This study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas. 展开更多
关键词 soft rock large deformation NPR anchor cable physical model numerical simulation compensation mechanics
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基于改进YOLOv7的猕猴桃果实识别优化
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作者 何翔 朱洪前 《林业与环境科学》 2024年第2期36-45,共10页
为了解决猕猴桃Actinidia chinensis果实识别过程中存在果实之间重叠导致的遮挡严重、检测结果易受叶片影响等问题,建立不同日照条件下的猕猴桃果实图像数据集,对YOLOv7模型做了3方面改进:将Backbone部分的卷积模块替换成GhostConv模块... 为了解决猕猴桃Actinidia chinensis果实识别过程中存在果实之间重叠导致的遮挡严重、检测结果易受叶片影响等问题,建立不同日照条件下的猕猴桃果实图像数据集,对YOLOv7模型做了3方面改进:将Backbone部分的卷积模块替换成GhostConv模块,在维持原有精度的程度上降低模型的参数量;针对猕猴桃果实之间存在大量重叠的情况,引入非极大值抑制NMS(Soft-NMS)策略提高检测框回归精度;融合SimAM注意力机制,增强模型对于高密度猕猴桃特征的提取能力。通过对比实验表明,优化后的模型与Faster RCNN相比,mAP值增加了12.7个百分点,检测速度提升106.8帧/s,综合性能较好,满足机器实时对于猕猴桃果实识别的需求。 展开更多
关键词 果实识别 YOLOv7 GhostConv Soft NMS SimAM
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Recent Progress of the Solar Wind Magnetosphere Ionosphere Link Explorer (SMILE) Mission
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作者 WANG Chi ESCOUBET Philippe +2 位作者 FORSYTH Colin LI Jing AGNOLON David 《空间科学学报》 CAS CSCD 北大核心 2024年第4期692-698,共7页
The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European Space Agency(ESA),aiming to understand the interaction ... The SMILE(Solar wind Magnetosphere Ionosphere Link Explorer)mission is a joint space science mission between the Chinese Academy of Sciences(CAS)and the European Space Agency(ESA),aiming to understand the interaction of the solar wind with the Earth’s magnetosphere in a global manner.As of May 2024,the SMILE mission is in phase-D with an expected launch date of September 2025.This report summarizes developments in the mission during the past two years. 展开更多
关键词 SMILE Soft X-ray Imager Ultra-Violet Imager Light Ion Analyzer MAGNETOMETER
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基于最大熵强化学习的最优渗透路径生成方法
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作者 王焱 王天荆 +1 位作者 沈航 白光伟 《计算机科学》 CSCD 北大核心 2024年第3期360-367,共8页
从攻击者角度分析入侵意图和渗透行为对于指导网络安全防御具有重要意义。然而,现有的渗透路径大多依据瞬时的网络环境构建,导致路径参考价值降低。针对该问题,文中提出了一种基于最大熵强化学习的最优渗透路径生成方法,该方法可以在网... 从攻击者角度分析入侵意图和渗透行为对于指导网络安全防御具有重要意义。然而,现有的渗透路径大多依据瞬时的网络环境构建,导致路径参考价值降低。针对该问题,文中提出了一种基于最大熵强化学习的最优渗透路径生成方法,该方法可以在网络环境动态变化的情况下,以探索的形式捕获多种模式的近似最优行为。首先,依据攻击图和漏洞评分对渗透过程进行建模,通过量化攻击获益来刻画渗透行为的威胁程度;然后,考虑到入侵行为的复杂性,开发基于最大熵模型的Soft Q-学习方法,通过控制熵值和奖励的重要程度来保证求解渗透路径的过程具有稳定性;最后将该方法应用于动态变化的测试环境中,生成高可用的渗透路径。仿真实验结果表明,相比于现有基于强化学习的基准方法,所提方法具有更强的环境适应性,能够以更低的代价生成更高收益的渗透路径。 展开更多
关键词 最大熵强化学习 攻击图 Soft Q-学习 渗透路径
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The full lifecycle management of scientific data at Hefei Light Source soft X-ray microscopy station
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作者 Haishan Yu Lei Cui +4 位作者 Zhen Zhang Guang Lin Xiaokang Sun DaDi Zhang Gongfa Liu 《中国科学技术大学学报》 CSCD 北大核心 2024年第11期2-7,1,66,共8页
Hefei Light Source(HLS)is a synchrotron radiation light source that primarily produces vacuum ultraviolet and soft X-rays.It currently consists of ten experimental stations,including a soft X-ray microscopy station.As... Hefei Light Source(HLS)is a synchrotron radiation light source that primarily produces vacuum ultraviolet and soft X-rays.It currently consists of ten experimental stations,including a soft X-ray microscopy station.As part of its on-going efforts to establish a centralized scientific data management platform,HLS is in the process of developing a test sys-tem that covers the entire lifecycle of scientific data,including data generation,acquisition,processing,analysis,and de-struction.However,the instruments used in the soft X-ray microscopy experimental station rely on commercial propriet-ary software for data acquisition and processing.We developed a semi-automatic data acquisition program to facilitate the integration of soft X-ray microscopy stations into a centralized scientific data management platform.Additionally,we cre-ated an online data processing platform to assist users in analyzing their scientific data.The system we developed and de-ployed meets the design requirements,successfully integrating the soft X-ray microscopy station into the full lifecycle management of scientific data. 展开更多
关键词 Hefei Light Source soft X-ray microscopy full lifecycle data acquisition data processing scientific data
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单目移动拍摄下基于人体部位的行人检测 被引量:10
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作者 田广 戚飞虎 +2 位作者 朱文佳 毛欣 陈磐君 《系统仿真学报》 EI CAS CSCD 北大核心 2006年第10期2906-2910,共5页
在摄像机安装在一个自由移动的平台的环境里,如汽车,检测行人变得非常困难,特别是当行人所处的场景比较复杂时。针对这种应用环境,文中提出了一种coarse-to-fine的行人检测方法。本方法把一个人建模成人体自然部位的组装,所用部位包括头... 在摄像机安装在一个自由移动的平台的环境里,如汽车,检测行人变得非常困难,特别是当行人所处的场景比较复杂时。针对这种应用环境,文中提出了一种coarse-to-fine的行人检测方法。本方法把一个人建模成人体自然部位的组装,所用部位包括头肩(head-shoulder),躯干(torso),腿(leg)。采用绝对值haar-like特征集和Edgelet特征集[1]。在这些特征集上,我们用SoftCascade[2]训练各个部位检测器和全身检测器(full-body)。在本算法中,首先由full-body检测器产生行人候选。然后,基于贝叶斯决策的组合算法进一步确定候选者中的行人。实验结果表明本算法有很好的检测性能,能在杂乱的自然场景中有效的检测行人。 展开更多
关键词 基于部位的行人检测 SOFT CASCADE 贝叶斯决策 概率组合
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基于分层强化学习的无人机空战多维决策 被引量:15
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作者 张建东 王鼎涵 +3 位作者 杨啟明 史国庆 陆屹 张耀中 《兵工学报》 EI CAS CSCD 北大核心 2023年第6期1547-1563,共17页
针对无人机空战过程中面临的智能决策问题,基于分层强化学习架构建立无人机智能空战的多维决策模型。将空战自主决策由单一维度的机动决策扩展到雷达开关、主动干扰、队形转换、目标探测、目标追踪、干扰规避、武器选择等多个维度,实现... 针对无人机空战过程中面临的智能决策问题,基于分层强化学习架构建立无人机智能空战的多维决策模型。将空战自主决策由单一维度的机动决策扩展到雷达开关、主动干扰、队形转换、目标探测、目标追踪、干扰规避、武器选择等多个维度,实现空战主要环节的自主决策;为解决维度扩展后决策模型状态空间复杂度、学习效率低的问题,结合Soft Actor-Critic算法和专家经验训练和建立元策略组,并改进传统的Option-Critic算法,设计优化策略终止函数,提高策略的切换的灵活性,实现空战中多个维度决策的无缝切换。实验结果表明,该模型在无人机空战全流程的多维度决策问题中具有较好的对抗效果,能够控制智能体根据不同的战场态势灵活切换干扰、搜索、打击、规避等策略,达到提升传统算法性能和提高解决复杂决策效率的目的。 展开更多
关键词 无人机空战 多维决策 分层强化学习 Soft Actor-Critic算法 Option-Critic算法
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混合动力变速箱齿轮修形优化及试验验证 被引量:3
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作者 潘公宇 王宪锰 +1 位作者 李东 梁艳春 《河南科技大学学报(自然科学版)》 CAS 北大核心 2016年第3期10-14,4-5,共5页
深度混合动力变速箱内的齿轮啮合产生的激振力引起箱体振动,齿轮接触状况不良噪音过大是变速箱的主要噪声来源。运用Kiss soft软件,建立了混合动力齿轮传动系统仿真模型,选取齿廓修形和齿向修形相结合的修形方案对齿轮进行优化改进,改... 深度混合动力变速箱内的齿轮啮合产生的激振力引起箱体振动,齿轮接触状况不良噪音过大是变速箱的主要噪声来源。运用Kiss soft软件,建立了混合动力齿轮传动系统仿真模型,选取齿廓修形和齿向修形相结合的修形方案对齿轮进行优化改进,改善齿轮齿面接触状况和齿轮传动平稳性。为验证齿轮修形的优化效果,对比齿轮优化前后箱体的噪声情况,选取特定纯电动工况下,对混合动力系统进行噪声试验。试验结果表明:在齿轮修形优化之后,箱体的噪音明显降低,噪声、振动和声振粗糙度(noise,vibration,harshness,NVH)性能得到明显改善。 展开更多
关键词 混合动力变速箱 NVH 齿轮修形 KISS soft软件 噪声试验
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反相胶团软模板法制备氯化银晶体纳米线研究 被引量:2
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作者 吴庆生 郑能武 丁亚平 《人工晶体学报》 EI CAS CSCD 北大核心 2000年第S1期150-,共1页
The nanosystem has received considerable attention because of its peculiar pheno mena,which is different from macroscopy and microscopy. At present,the upsurge o f researching nanomaterials has shifted from nano parti... The nanosystem has received considerable attention because of its peculiar pheno mena,which is different from macroscopy and microscopy. At present,the upsurge o f researching nanomaterials has shifted from nano particles to one dimensional na nosystem,such as nanowires,nanotubes,and so on.Seen from literatures, the repor ts on carbon nanotubes wer e more,on nanowires were less,and on transition metallic salt nanowires were noth ing .In this paper,AgCl nanocrystalline wires were successfully synthesized by Rever s e Micelle soft Templates, which will open a new way for the synthesis and applic ation of one dimensional nanomaterials. 展开更多
关键词 AGCL crystal NANOCRYSTALLINE WIRES reverse MICELLE soft templates
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基于SAC模型的改进遗传算法求解TSP问题 被引量:17
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作者 陈斌 刘卫国 《计算机科学与探索》 CSCD 北大核心 2021年第9期1680-1693,共14页
遗传算法(GA)的全局搜索能力强,易于操作,但其收敛速度慢,易陷入局部最优值。针对以上问题,利用深度强化学习模型SAC对遗传算法进行改进,并将其应用至旅行商问题(TSP)的求解。改进算法将种群作为与智能体(agent)交互的环境,引入贪心算... 遗传算法(GA)的全局搜索能力强,易于操作,但其收敛速度慢,易陷入局部最优值。针对以上问题,利用深度强化学习模型SAC对遗传算法进行改进,并将其应用至旅行商问题(TSP)的求解。改进算法将种群作为与智能体(agent)交互的环境,引入贪心算法对环境进行初始化,使用改进后的交叉与变异运算作为agent的动作空间,将种群的进化过程视为一个整体,以最大化种群进化过程的累计奖励为目标,结合当前种群个体适应度情况,采用基于SAC的策略梯度算法,生成控制种群进化的动作策略,合理运用遗传算法的全局和局部搜索能力,优化种群的进化过程,平衡种群收敛速度与遗传操作次数之间的关系。对TSPLIB实例的实验结果表明,改进的遗传算法可有效地避免陷入局部最优解,在提高种群收敛速度的同时,减少寻优过程的迭代次数。 展开更多
关键词 强化学习 遗传算法(GA) 旅行商问题(TSP) 深度策略梯度 soft actor-critic(SAC)模型
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降低PSE猪肉发生的营养调控措施 被引量:1
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作者 张云琦 周安国 胡民强 《饲料工业》 2008年第5期48-52,共5页
1 概述 猪肉按肉质一般划分为4类:第一类是PSE(pale,soft,exudative)肉,表现为肉色苍白、质地松软、表面有汁液渗出;第二类是RSE(reddish-pink,soft,exuddative)肉,其猪肉的肉色正常,但具过多的水分损失,其硬度、渗出性... 1 概述 猪肉按肉质一般划分为4类:第一类是PSE(pale,soft,exudative)肉,表现为肉色苍白、质地松软、表面有汁液渗出;第二类是RSE(reddish-pink,soft,exuddative)肉,其猪肉的肉色正常,但具过多的水分损失,其硬度、渗出性如PSE猪肉;第三类是RFN(reddish-pink,firm,non-exudative)肉,属正常肉品;第四类是DFD(dark,firm,Dry)肉,表现为暗黑、坚硬、干燥。有关此4类肉的区分标准:①PSE:L*〉50,滴水损失〉6%;②RSE:L*≤50,滴水损失〉6%;③RFN:L*≤50,滴水损失〈6%;④DFD:L*≤43,滴水损失〈6%。 展开更多
关键词 PSE猪肉 营养调控措施 滴水损失 SOFT 水分损失 区分标准 渗出性 RSE
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