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链路及节点多属性融合的低轨卫星网络路由算法

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计算机工程与应用 2024年第18期60卷 266-274页

作者：孙正阳杜晔李桂领黎妹红北京交通大学智能交通数据安全与隐私保护技术北京市重点实验室北京100044 北京交通大学计算机与信息技术学院北京100044 教育部教育考试院北京100084

针对低轨卫星网络面对破坏性事件系统性能损失多、通信延迟和丢包率高的问题,提出了基于多属性的低轨卫星网络多路径路由算法。在采用虚拟拓扑方案仿真的低轨卫星星座中,计算源节点与目标节点之间的多条可行路径,该算法融合卫星间链路... 详细信息

针对低轨卫星网络面对破坏性事件系统性能损失多、通信延迟和丢包率高的问题,提出了基于多属性的低轨卫星网络多路径路由算法。在采用虚拟拓扑方案仿真的低轨卫星星座中,计算源节点与目标节点之间的多条可行路径,该算法融合卫星间链路属性和相邻卫星节点属性构建路径的传输成本模型,自适应调整两类属性对传输成本的影响权重,每颗卫星将路径传输成本的归一化结果作为通过该路径转发报文的概率,并独立进行分布式的路由选择。仿真结果表明,与经典的低轨卫星网络多路径路由算法相比,无论网络负载较大发生拥塞时,还是卫星遭受网络攻击或出现故障时,该算法性能下降缓慢,丢包率和平均端到端延迟更低,且具有良好的负载均衡能力,有效增强了路由的可用性。

关键词：低轨卫星网络多路径路由链路属性卫星属性负载均衡

基于UGC数据的农业文化遗产地景观意象感知研究——以龙胜龙脊梯田为例

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桂林理工大学学报 2024年第2期44卷 357-365页

作者：樊亚明孙正阳张晓莎郑文俊桂林理工大学旅游与风景园林学院广西桂林541006 邢台市交通建设集团投资有限公司河北邢台054001

以广西龙胜龙脊梯田为例,基于文本和图片数据,从自然景观意象、人工景观意象、文化景观意象三大维度深入解析游客的认知意象、情感意象和整体意象的感知特征。结果表明:龙脊梯田农业文化遗产地景观意象感知呈现物质景观强、非物质景观... 详细信息

以广西龙胜龙脊梯田为例,基于文本和图片数据,从自然景观意象、人工景观意象、文化景观意象三大维度深入解析游客的认知意象、情感意象和整体意象的感知特征。结果表明:龙脊梯田农业文化遗产地景观意象感知呈现物质景观强、非物质景观弱的总体特征;农业景观、居民建筑占据农业文化遗产地景观意象网络的主导地位,两者间的关联性也最高,是认知意象的主要类型,而民俗节事、饮食文化、民间艺术、水系景观等意象维度词频较低,与其他意象维度的关联较少,认知意象感知较弱;对农业景观、居民建筑、饮食文化等意象维度以“满意”等积极情感意象感知为主,“辛苦”“可惜”等消极情感主要出现在道路交通的情感意象感知上;基于IPA整体意象感知分析显示,农业景观、居民建筑、自然风光的重要性与满意度都高,山体景观、水系景观、饮食文化的重要性低而满意度高,民俗节事、民间艺术、社区氛围等重要性与满意度较低。

关键词：景观意象旅游感知 UGC 农业文化遗产地龙脊梯田

基于EDEM的砂卵石地层盾构刀具磨损特征研究

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岩土工程学报 2024年第10期46卷 2212-2220页

作者：张晋勋李博江玉生江华殷明伦孙正阳北京城建集团有限责任公司北京100088 中国矿业大学(北京)力学与建筑工程学院北京100083

为揭示砂卵石地层土压平衡盾构典型刀具的磨损特征,指导该地层中盾构刀具的设计、布置等关键问题。采用室内三轴试验及数值离散元软件(EDEM)仿真分析,标定了颗粒-刀具磨损接触参数。依托北京新机场“磁各庄-1号风井”砂卵石盾构工程,构... 详细信息

为揭示砂卵石地层土压平衡盾构典型刀具的磨损特征,指导该地层中盾构刀具的设计、布置等关键问题。采用室内三轴试验及数值离散元软件(EDEM)仿真分析,标定了颗粒-刀具磨损接触参数。依托北京新机场“磁各庄-1号风井”砂卵石盾构工程,构建了砂卵石地层EDEM数值盾构模型,可视化了砂卵石地层土压平衡盾构中典型刀具(楔犁刀、刮刀)的磨损特征,通过实际工程对模型进行了验证。研究表明:(1)以犁松原状砂卵石土为目的的楔犁刀具是掘进主切削刀具,表现为刀头合金表面以及刃角处连续的摩擦磨损形式,磨损量较大;(2)以剥落输排为目的刮刀主要表现为刀身迎土面以及刀头合金表面随机的点蚀磨损,磨损量较小;(3)刀盘径向刀具的磨损量随轨迹半径及刀体高度的增加而增大,同轨迹上高刀的磨损系数高于低刀,高刀对低刀的磨损有保护作用;刀盘径向刀具和环向刀具的“梯次化”布置可延长盾构单次连续掘进距离。

关键词：砂卵石地层盾构刀具磨损特征 EDEM数值仿真设计与布置

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复杂交错格栅的滤芯托架热流道注塑模具设计

工程塑料应用 2024年第5期52卷 115-120页

作者：刘晓坤孙正阳于洋洋陈晔杨栋梁季宁天津仁爱学院机械工程学院天津301636 天津圣达辰洋汽车部件有限公司天津301600 天津市生华厚德科技有限公司天津300182 天津大学内燃机燃烧学国家重点实验室天津300072

针对复杂交错薄壁格栅的滤芯托架在注塑成型时极易造成困气和脱模时易变形的问题,设计了点浇口二板式热流道注塑模具。首先,对滤芯托架进行结构设计和材料成分分析,基于CAE技术,考虑复杂结构形式及注塑机吨位选择因素,确定了最佳浇口位... 详细信息

针对复杂交错薄壁格栅的滤芯托架在注塑成型时极易造成困气和脱模时易变形的问题,设计了点浇口二板式热流道注塑模具。首先,对滤芯托架进行结构设计和材料成分分析,基于CAE技术,考虑复杂结构形式及注塑机吨位选择因素,确定了最佳浇口位置;其次,考虑冷却+填充+保压+翘曲过程,分析了流动前沿温度与气穴现象,通过局部结构设计和排气方式增加配合间隙,有效解决排气问题。高效的冷却回路设计缩短了冷却时间,提高了生产效率。巧妙地设计了顶出机构,七个推件块有差别布置,同时中间位置也设计了顶出机构,在顶出时保持方向一致性,解决了交错薄壁格栅结构复杂和表面积大带来的翘曲量大和体积收缩大的问题。在注塑机上开展模具工作试模,采用最优拉丁超立方方法采样工艺参数数据,依次输入注塑机面板内,寻优后得到最优工艺参数。生产实践证明,该模具结构合理,工作过程稳定可靠,可为具有交错薄壁格栅结构特征的相似结构的产品注塑模具设计提供重要参考。

关键词：格栅交错薄壁滤芯托架热流道模具结构

Experimental investigation on flow asymmetry in solid entrance region of a square circulating fluidized bed

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Particuology 2009年第6期7卷 483-490页

作者： zhengyang Wang Shaozeng sun Hao Chen Qigang Deng Guangbo Zhao Shaohua Wu Combustion Engineering Research Institute Harbin Institute of Technology Harbin 150001 China

To study the influence of back feeding particles on gas-solid flow in the riser, this paper investigated the flow asymmetry in the solid entrance region of a fluidized bed by particle concentration/velocity measurements in a cold square circulating fluidized beds （CFB）. The pressure drop distribution along the riser and the saturation carrying capacity of gas for Geldart-B type particles were first analyzed. Under the condition of u0 = 4 m/s and Gs = 21 kg/（m^2 s）, the back feeding particles were found to penetrate the lean gas-solid flow near the entrance （rear） wall before reaching the opposite （front） wall, thus leading to a relatively denser region near the front wall in the bottom bed. Higher solid circulation rate （u0 =4 m/s, Gs = 33 kg/（m^2 s）） resulted in a higher particle concentration in the riser. However the back feeding particles with higher momentum increased the asymmetry of the particle concentration/velocity profile in the solid entrance region. Lower air velocity （u0 =3.2 m/s） and Gs =21 kg/（m2 s）, beyond the saturation carrying capacity of gas, induced an S-shaped axial solid distribution with a denser bottom zone. This limited the penetration of the back feeding particles and forced the flnidizing air to flow in the central region, thus leading to a higher solid holdup near the rear wall. Under the conditions of uo = 4 m/s and Gs = 21 kg/（m^2 s）, addition of coarse particles （dp= 1145 μm） into the bed made the radial distribution of solids more symmetrical.

关键词： Square circulating fluidized bed Solid entrance region Flow asymmetry Experimental investigation

基于RBF和LSGRG的滤芯托架注塑成型质量控制与优化

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工程塑料应用 2024年第8期52卷 90-95页

作者：刘晓坤孙正阳季宁盛中庆于洋洋张学玲天津仁爱学院机械工程学院天津301636 天津圣达辰洋汽车部件有限公司天津301600 天津市生华厚德科技有限公司天津300182 天津大学内燃机燃烧学国家重点实验室天津300072

针对汽车用复杂交错薄壁格栅的滤芯托架体积收缩率大和生产能耗高的问题,采用有限元仿真分析方法,建立了复杂交错薄壁格栅的滤芯托架仿真分析的有限元模型,对塑件的体积收缩率和注塑过程中的最大锁模力进行了优化,以提高塑件成型质量和... 详细信息

针对汽车用复杂交错薄壁格栅的滤芯托架体积收缩率大和生产能耗高的问题,采用有限元仿真分析方法,建立了复杂交错薄壁格栅的滤芯托架仿真分析的有限元模型,对塑件的体积收缩率和注塑过程中的最大锁模力进行了优化,以提高塑件成型质量和降低生产能耗。首先,基于最优拉丁超立方抽样(OLHS)方法和径向基函数(RBF)神经网络模型建立预测模型并对模型精度进行了验证;其次,通过分析20组计算数据并结合工程经验发现体积收缩率和最大锁模力呈相互冲突的关系,且对成型质量和能耗有较大的影响,为此采用大规模广义降阶梯度(LSGRG)技术对预测模型进行多目标寻优并得到最优的工艺参数组合,经过LSGRG方法优化的最大锁模力降低了10.30%,体积收缩率降低了27.61%,优化效果显著。最后,在注塑机上应用优化后的注塑工艺参数生产出了复杂交错薄壁格栅的滤芯托架,产品质量符合要求。提出的基于RBF神经网络模型和LSGRG技术的联合多目标优化方法可为同类型塑件的成型质量控制与优化提供借鉴。

关键词：滤芯托架多目标优化最优拉丁超立方抽样径向基函数神经网络 LSGRG技术

Super-resolution diffractive neural network for alloptical direction of arrival estimation beyond diffraction limits

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Light(Science & Applications) 2024年第8期13卷 1602-1614页

作者： Sheng Gao Hang Chen Yichen Wang zhengyang Duan Haiou Zhang Zhi sun Yuan Shen Xing Lin Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Wireless sensing of the wave propagation direction from radio sources lays the foundation for communication,radar,navigation,***,the existing signal processing paradigm for the direction of arrival estimation requires the radio frequency electronic circuit to demodulate and sample the multichannel baseband signals followed by a complicated computing process,which places the fundamental limit on its sensing speed and energy ***,we propose the super-resolution diffractive neural networks(S-DNN)to process electromagnetic(EM)waves directly for the DOA estimation at the speed of *** multilayer meta-structures of S-DNN generate super-oscillatory angular responses in local angular regions that can perform the all-optical DOA estimation with angular resolutions beyond the diffraction *** spatial-temporal multiplexing of passive and reconfigurable S-DNNs is utilized to achieve high-resolution DOA estimation over a wide field of *** S-DNN is validated for the DOA estimation of multiple radio sources over 5 GHz frequency bandwidth with estimation latency over two to four orders of magnitude lower than the state-of-the-art commercial devices in *** results achieve the angular resolution over an order of magnitude,experimentally demonstrated with four times,higher than diffraction-limited *** also apply S-DNN’s edge computing capability,assisted by reconfigurable intelligent surfaces,for extremely low-latency integrated sensing and communication with low power *** work is a significant step towards utilizing photonic computing processors to facilitate various wireless sensing and communication tasks with advantages in both computing paradigms and performance over electronic computing.

关键词： beyond optical network

Targeting LTA4H facilitates the reshaping of the immune microenvironment mediated by CCL5 and sensitizes ovarian cancer to Cisplatin

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Science China(Life Sciences) 2024年第6期67卷 1226-1241页

作者： zhengyang Guo Jiaqi Huang Xiao Huo Chen Huang Xiaotong Yu Yan sun Yanfang Li Tianhui He Hongyan Guo Jianling Yang Lixiang Xue Cancer Center of Peking University Third Hospital Beijing 100191China Center of Basic Medical Research Institute of Medical Innovation and ResearchPeking University Third HospitalBeijing 100191China Peking University Third Hospital Cancer Center Department of Radiation OncologyPeking University Third HospitalBeijing 100191China Department of Obstetrics and Gynecology Peking University Third HospitalBeijing 100191China

Ovarian cancer is the most lethal and aggressive gynecological cancer with a high recurrence rate and is often diagnosed *** ovarian cancer,multiple metabolic enzymes of lipid metabolism are abnormally expressed,resulting in metabolism *** a characteristic pathway in polyunsaturated fatty acid(PUFA)metabolism,arachidonic acid(AA)metabolism is disturbed in ovarian ***,we established a 10-gene signature model to evaluate the prognostic risk of PUFA-related *** 10-gene signature has strong robustness and can play a stable predictive role in datasets of various platforms(TCGA,ICGC,and GSE17260).The high association between the risk subgroups and clinical characteristics indicated a good performance of the *** data further indicated that the high expression of LTA4H was positively correlated with poor prognosis in ovarian *** of LTA4H enhanced sensitivity to Cisplatin and modified the characteristics of immune cell infiltration in ovarian ***,our results indicate that CCL5 was involved in the aberrant metabolism of the AA/LTA4H axis,which contributes to the reduction of tumor-infiltrating CD8+T cells and immune escape in ovarian *** findings provide new insights into the prognosis and potential target of LTA4H/CCL5 in treating ovarian cancer.

关键词： ovarian cancer polyunsaturated fatty acids prognostic risk model LTA4H tumor immunity CCL5

Resistance index and browning mechanism of apple peel under high temperature stress

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Horticultural Plant Journal 2024年第2期10卷 305-317页

作者： Hui Wang Shuhui Zhang Zidun Wang Dongmei Li Leiyu Yan Yifeng Feng Xiaojie Liu Rongxin Chen Wenmin Fan Lulong sun zhengyang Zhao College of Horticulture Northwest A&F UniversityYanglingShaanxi 712100China College of Horticultural Science and Engineering Shandong Agricultural University State Key Laboratory of Crop BiologyTai'anShandong 271018China

Apples are one of the most important economic crops *** of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and *** took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was *** results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 *** determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different *** was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype ***,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing *** content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in ***,transient and stable MdPPO1 overexpression significantly promoted peel *** transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature ***,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browni

关键词： Malus domestica Borkh High temperature stress Peel Browning MdPPO1