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Initial Assessment of LEO-Augmented GPS RTK in Signal-Degraded Environment

IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2020年第7期E103A卷 942-946页

作者： Hu, Weisheng Hou, Huiling Xie, Zhuochen Liang, xuwen he, Xiaohe Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai Peoples R China Univ Chinese Acad Sci Beijing Peoples R China Chinese Acad Sci Shanghai Engn Ctr Microsatellites Shanghai Peoples R China ShanghaiTech Univ Sch Informat Sci & Technol Shanghai Peoples R China

We simulate some scenarios that 2/3 LEO satellites enhance 3/4/5 GPS satellites, to assess LEO-augmented GPS RTK positioning in signal-degraded environment. The e ffects of LEO-augmented GPS RTK in terms of reliabilit... 详细信息

关键词： LEO-augmented RTK signal-degrade environment DIA

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Research on the Performance of Multi-GNSS Medium Length Baseline RTK with LEO-Augmented

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IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES 2020年第5期E103A卷 780-784页

作者： Hu, Weisheng Liang, xuwen Hou, Huiling Xie, Zhuochen he, Xiaohe Chinese Acad Sci Shanghai Inst Microsyst & Informat Technol Shanghai Peoples R China Chinese Acad Sci Shanghai Engn Ctr Microsatellites Shanghai Peoples R China Univ Chinese Acad Sci Beijing Peoples R China ShanghaiTech Univ Sch Informat Sci & Technol Shanghai Peoples R China

In this letter, we simulate GNSS/LEO measurements and propose a process strategy for LEO-augmented GNSS medium length baseline RTK. Experiments show that, the performance of GNSS medium length baseline RTK can be significantly improved by introducing LEO satellites. The convergence speed of LEO-augmented GPS or BDS float solution maybe better than GPS/BDS combined under the conditions of similar satellite geometry. Besides, the RMS error of fixed solutions are improved to better than 4 cm from sub-decimeter level.

关键词： multi-GNSS LEO-augmented medium length baseline RTK

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利用慢病毒载体构建过表达人TCRP1基因的慢性髓系白血病K562细胞系及其生物学功能检测

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实用医学杂志 2023年第19期39卷 2456-2460,2468页

作者：刘孝荣何悦陈妍辛泽锋邓栩文钟惠锋陈运生深圳市儿童医院检验科广东深圳518034 深圳市儿童医院儿科研究所广东深圳518034 深圳市儿童医院血液肿瘤科广东深圳518034

目的利用慢病毒载体构建过表达人舌癌耐药相关基因(TCRP1)的慢性髓系白血病(CML)K562细胞系并检测其生物学功能。方法将TCRP1的重组质粒与包装质粒共转染293T细胞,收集病毒液测定滴度后感染K562细胞,使用嘌呤霉素筛选TCRP1过表达的细胞... 详细信息

目的利用慢病毒载体构建过表达人舌癌耐药相关基因(TCRP1)的慢性髓系白血病(CML)K562细胞系并检测其生物学功能。方法将TCRP1的重组质粒与包装质粒共转染293T细胞,收集病毒液测定滴度后感染K562细胞,使用嘌呤霉素筛选TCRP1过表达的细胞株K562/TCRP1,荧光定量PCR和Western blot方法检测TCRP1的表达,采用连续细胞计数法和CCK-8法分别对K562/TCRP1及其对照细胞株的增殖情况进行检测,并分析2个细胞株对不同浓度的伊马替尼(IM)的药物敏感性。结果TCRP1慢病毒表达载体成功转染进入K562细胞,荧光定量PCR和Western blot结果显示K562/TCRP1细胞株的TCRP1表达在mRNA水平和蛋白水平均显著高于对照组,连续细胞计数法和CCK-8法结果表明K562/TCRP1细胞的增殖能力和细胞活力增强,IM处理K562/TCRP1细胞的IC50值显著高于其对照细胞(P<0.05)。结论利用慢病毒载体成功构建了TCRP1过表达的K562细胞株,并且发现TCRP1的过表达可能增强K562细胞的增殖能力和IM耐药能力,为进一步探讨TCRP1在慢性髓系白血病发病机制中的可能作用提供基础。

关键词： TCRP1 过表达 K562细胞慢性髓系白血病

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基于改进注意力模块的船舶涂装缺陷检测方法

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江苏科技大学学报（自然科学版） 2024年第3期38卷 1-8页

作者：庞博卜赫男李磊周宏根景旭文江苏科技大学机械工程学院镇江212100

针对人工检测船舶缺陷效率低、传统检测网络准确率差的问题,提出一种基于改进注意力模块(improved convolutional block attention module, ICBAM)的船舶涂装缺陷检测方法.首先,YOLOv4在路径聚合网络中将深度可分离卷积代替常规卷积形成... 详细信息

针对人工检测船舶缺陷效率低、传统检测网络准确率差的问题,提出一种基于改进注意力模块(improved convolutional block attention module, ICBAM)的船舶涂装缺陷检测方法.首先,YOLOv4在路径聚合网络中将深度可分离卷积代替常规卷积形成IYOLOv4,减少模型计算量;其次,将ICBAM融入IYOLOv4的路径聚合网络Route层后形成ICBAM-IYOLOv4,ICBAM在通道上构建多频率通道改善全局平均池化,利用一维卷积代替全连接层聚合相邻通道间的信息,减少模型参数;然后,在空间上融合Inception v3思想和特征分层思想改善空洞卷积;最后,在船舶涂装缺陷样本数据增强的基础上,对ICBAM-IYOLOv4进行测试.实验结果表明:ICBAM-IYOLOv4相比其他算法,其损失值更低、收敛更快;平均精度均值(mean average precision, MAP)在训练集和测试集上分别提高了1.89%和1.91%.

关键词：船舶涂装缺陷检测特征分层多频率通道注意力模块深度可分离卷积一维卷积

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Compositional correlation and polymorphism in BaF2-PrF3 thin films deposited using electron-beam evaporation

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THIN SOLID FILMS 2019年 669卷 558-563页

作者： he, Weixiang Zheng, Weimin Xie, Ping Li, Bin Lv, xuwen Jing, Chao Liu, Dingquan Shanghai Univ Dept Phys Shanghai 200444 Peoples R China Shandong Univ Sch Space Sci & Phys Weihai 264209 Peoples R China Chinese Acad Sci Shanghai Inst Tech Phys Shanghai 200083 Peoples R China Shanghai Tech Univ Sch Phys Sci & Technol Shanghai 200031 Peoples R China

Infrared low-index evaporation materials are essential in the broadband antireflection coatings to reduce Fresnel reflections on the surfaces of infrared optical components. Although the layers of praseodymium fluoride (PrF3) show an excellent transparency and the lower refractive index n and extinction coefficient k in the spectral range of thermal infrared, the tensile stress presented in the layers prohibits PrF3 from being used as infrared low-index coating materials. A practical solution to reduce stress is to directly evaporate the admixture of PrF3 with alkaline fluorides, such as barium fluoride (BaF2). However, due to the significant difference of vapor pressures between PrF3 and BaF2, it is commonly difficult to congruently deposit PrF3-BaF2 thin films utilizing evaporating directly from a single source. Moreover, more details are unknown about the phase compositions of PrF3-BaF2 thin films. In our investigation, BaF2-PrF3 thin films were deposited using electron beam evaporation from the sintered ingots of PrF3 admixed with BaF2. The compositions of thin films were characterized using energy dispersive X-ray spectroscopy (EDX), the crystallographic structures were explored by X-ray-diffraction (XRD). It was revealed that the concentration of BaF2 in thin films can be correlated to that in the admixtures. Moreover, in addition to PrF3 and BaF2, the phase compositions in thin films include also secondary phases, such as PrOF, PrF4, Pr2F2, BaPrF6, and that of elemental Ba.

关键词： Infrared low -index evaporation materials BaF2-PrF3 Electron beam evaporation Compositional correlation Polymorphism

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神经网络预测磁絮凝处理矿井水效果的研究

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工业水处理 2018年第1期38卷 57-61页

作者：张晓航何绪文王浩张斯宇孙艺欣李福勤刘涛中国矿业大学(北京)化学与环境工程学院北京100083 河北工程大学能源与环境工程学院河北邯郸056038

构建了磁絮凝处理矿井水实验装置,并使用RS485接口经串口协议与计算机MFC控制程序交换数据。根据实验装置所得数据,采用C++调用Matlab Engine实现GA-BP和GRNN神经网络的训练、预测与准确度的分析。由分析可知,GA-BP神经网络初始化参数较... 详细信息

构建了磁絮凝处理矿井水实验装置,并使用RS485接口经串口协议与计算机MFC控制程序交换数据。根据实验装置所得数据,采用C++调用Matlab Engine实现GA-BP和GRNN神经网络的训练、预测与准确度的分析。由分析可知,GA-BP神经网络初始化参数较多,预测结果平均绝对误差为21.849,个体适应度在进化次数为35时趋于平稳,适应度达到82%。GRNN神经网络初始化仅需要调整光滑因子,当光滑因子取0.75时,预测平均绝对误差为10.726。通过比较GA-BP与GRNN神经网络的R^2和RMSE的数值,可知GRNN准确性更高,在磁絮凝处理含悬浮物矿井水中适用性更强。

关键词：磁絮凝神经网络矿井水

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Synthesis of hybrid dendritic mesoporous silica titanium nanoparticles to stabilize Pickering emulsions for enhanced oil recovery

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COLLOIDS AND SURFACES A-PHYSICOCheMICAL AND ENGINEERING ASPECTS 2021年 628卷

作者： Jia, Han he, Juan Xu, Yingbiao Wang, Tingyi Zhang, Lingyu Fan, Fangning Qin, xuwen Li, Zhe Lv, Kaihe Wang, Yabin China Univ Petr East China Sch Petr Engn Shandong Key Lab Oilfield Chem Qingdao 266580 Peoples R China China Univ Petr East China Minist Educ Key Lab Unconvent Oil & Gas Dev Qingdao 266580 Peoples R China SINOPEC Technol Inspect Ctr Shengli Oilfield Co Dongying 257000 Peoples R China Yanan Univ Coll Chem & Chem Engn Shaanxi Key Lab Chem React Engn Yanan 716000 Peoples R China

Nanoparticles stabilized Pickering emulsions have been widely applied in various fields. The size and morphology of nanoparticles are regarded as crucial factors for the emulsion stability. In this study, the dendritic mesoporous silica nanoparticles (DMSNs) and two kinds of hybrid dendritic mesoporous silica titanium nanoparticles (DMSTNs-0.01 and DMSTNs-0.03) have been successfully prepared and investigated for their potential application to stabilize Pickering emulsions. Scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and UV-Vis diffuse reflectance spectra are employed to confirm the successful fabrication of the nanoparticles. The stability of DMSNs and DMSTNs stabilized emulsions are systematically evaluated via the optical microscopy and static multiple light scattering. The DMSTNs-0.01 displays the greatest ability to stabilize emulsions. N-2 physisorption and atomic force microscopy demonstrate the stability of Pickering emulsions is closely related to the specific surface area and surface roughness of nanoparticles. Moreover, DMSTNs-0.01 stabilized O/W Pickering emulsions show satisfactory displacement performance (tertiary oil recovery of 14.05%) in core flooding experiments. Microscopic visualization tests further indicate the emulsions can effectively block the high permeability channels generated by initial water flooding to increase the flowing resistance and then cause the flow diversion of the repellent fluid to enlarge the sweep area.

关键词： Hybrid dendritic mesoporous silica titanium nanoparticles Pickering emulsions Surface roughness Specific surface area EOR

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Investigation of energetic ion losses induced by long-lived saturated internal mode with energetic particle diagnostics in the HL-2A tokamak

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NUCLEAR FUSION 2023年第8期63卷 086014-086014页

作者： Zhang, Jie Zhang, Yipo Chen, Wei Cheng, Shikui Ogawa, Kunihiro he, Xiaofei Wang, Yongqin Liu, Yi Xu, Min Isobe, Mitsutaka Zhu, Yuxuan Zhan, xuwen Zhou, Jianhang Zhang, Jinglong Liu, Liang he, Xiaoxue Li, Dong Li, Yonggao Guo, Wenping Yu, Liming Hao, Guangzhou Li, Bo Shi, Zhongbing Ji, Xiaoquan Zhong, Wulv Southwestern Inst Phys POB 432 Chengdu 610041 Peoples R China Natl Inst Fus Sci Natl Inst Nat Sci Toki Japan SOKENDAI Grad Univ Adv Studies Toki Japan Chengdu Univ Technol Coll Nucl Technol & Automation Engn Chengdu 610059 Peoples R China

Several sets of energetic particle diagnostics, including a set of neutron flux monitoring systems, a solid-state neutral particle analyzer and a fast ion loss probe (FILP), have been used to investigate the energetic ion losses induced by the long-lived saturated internal mode (LLM) in the HL-2A tokamak. Clear experimental evidence for different levels of energetic ion losses induced by LLM, sawtooth and minor disruption has been observed. A numerical calculation for the evolution of neutron emissions was carried out with the FBURN code, and it shows that the neutron emission drop rate linearly increases with the LLM amplitude and no threshold perturbation amplitude exists, illustrating that the loss mechanism for LLM induced energetic ion loss is dominantly convective. In addition, measurement results of the FILP demonstrate that LLM tends to expel energetic ions with relatively low energy (E < 27 keV) and high pitch angle (? > 60(?)), and can suppress the prompt loss of energetic ions with high energy and low pitch angle to a certain degree. Furthermore, the physical process for LLM induced energetic ion loss can be explained by orbit calculations, which show that LLM induced lost energetic ions will transport from center to peripheral region first, and then get lost out of plasma. The experimental observations are successfully reproduced by calculations using the ORBIT code combined with both the NUBEAM code and the MARS-K code. The paper clearly describes the whole physical process of LLM induced energetic ion loss for the first time in the HL-2A tokamak.

关键词： energetic ion loss long-lived saturated internal mode neutron flux measurement neutral particle analyzer fast ion loss probe

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头颈部低分化脊索瘤临床病理分析和预后评估

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临床肿瘤学杂志 2024年第5期29卷 489-493页

作者：何文源赖续文曾伟鹏喻玲王卓才王蔚中国人民解放军南部战区总医院病理科广州510010

目的探讨低分化脊索瘤(PDC)的临床病理特点及鉴别诊断,并评估其预后。方法收集2006年1月至2022年6月解放军南部战区总医院6例头颈部PDC患者的临床和影像学资料,采用he染色、免疫组织化学染色和荧光原位杂交(FISH)检测,探讨其临床病理特... 详细信息

目的探讨低分化脊索瘤(PDC)的临床病理特点及鉴别诊断,并评估其预后。方法收集2006年1月至2022年6月解放军南部战区总医院6例头颈部PDC患者的临床和影像学资料,采用he染色、免疫组织化学染色和荧光原位杂交(FISH)检测,探讨其临床病理特征及预后。结果6例患者中,女性5例,男性1例;年龄4~37岁,中位年龄15岁;肿瘤位于颈椎4例,颅底2例。镜下上皮样或梭形肿瘤细胞呈巢团状或弥漫片状分布,巢团中央可见坏死,部分瘤细胞呈横纹肌样,细胞核呈囊泡状,核仁明显,核分裂象多少不等,间质淋巴细胞、浆细胞及中性粒细胞浸润。免疫表型:6例肿瘤细胞CK、EMA、Vimentin和Brachyury均弥漫阳性,SMARCB1/INI1核表达均缺失,Ki-67增殖指数10%~50%不等。5例患者行肿瘤大部分切除术,1例仅放化疗。5例患者获随访,分别于首诊后2~17个月死亡,中位生存时间5个月。结论颈椎亦是PDC好发部位,常因缺乏经典脊索瘤形态特征而易于误诊,但免疫表型与经典脊索瘤相同,SMARCB1/INI1核表达缺失是重要诊断线索。PDC易复发及转移,预后差。

关键词：脊索瘤低分化颈椎 SMARCB1/INI1 预后

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基于协作关系的智能反射面通信增强模型

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激光与光电子学进展 2021年第23期58卷 49-54页

作者：韩博宇梁旭文谢卓辰杜旭贺晓赫中国科学院微小卫星创新研究院上海201203 中国科学院大学北京100049 上海科技大学信息学院上海201210

智能反射面(IRS)是一种集成大量低成本、低损耗、可重构无源反射元件的平面,可以智能地配置信号传播,提高无线网络的频谱效率和能量效率。即在获知用户位置后,利用优化算法计算信号的反射相位,提高用户接收到的功率。提出了一种在室内... 详细信息

智能反射面(IRS)是一种集成大量低成本、低损耗、可重构无源反射元件的平面,可以智能地配置信号传播,提高无线网络的频谱效率和能量效率。即在获知用户位置后,利用优化算法计算信号的反射相位,提高用户接收到的功率。提出了一种在室内小范围环境下具有协作关系的双IRS模型,利用两个具有协作关系的IRS增强基站与用户间直连链路不可用时用户接收到的信号功率。用两个IRS的移相矩阵作为优化变量,最大化用户接收到的信号功率。该问题的建模为非凸网络优化问题,采用基于内点优化的求解器进行仿真,同时与无协作关系模型的性能进行了对比。对比结果表明,在室内小范围环境下,具有协作关系的模型比无协作关系模型的增强效果更好。

关键词：光纤光学网络优化智能反射面协作关系非凸优化

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