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Determination of global geodetic parameters using satellite laser ranging to Galileo,GLONASS,and BeiDou satellites

Satellite Navigation 2024年第1期5卷 240-257页

作者： Xingxing Li jiaqing Lou Yongqiang Yuan jiaqi wu Keke Zhang School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079HubeiChina

The new Global Navigation Satellite System(GNSS)satellites,including GLONASS,Galileo,and BeiDou system,are equipped with Laser Retroreflector Arrays(LRA)to support Satellite Laser Ranging(SLR)tracking,which contributes to the estimation of global geodetic *** this study,we estimate the global geodetic parameters using the SLR observations to GNSS satellites and also investigate the effects of different data processing strategies on the estimated Earth Rotation Parameters(ERP),geocenter motion,and terrestrial *** results indicate that setting range bias parameters for each satellite-station pair can effectively account for the satellite-specific biases induced by LRAs,leading to smaller Root Mean Square Errors(RMSE)of the post-fit SLR ***,estimating the range biases for each satellite-station pair improves the accuracy of the estimated station coordinates and *** also examine the impact of different arc lengths on the estimates of ERP,geocenter motion,and terrestrial *** results show that extending arc length can significantly reduce the formal error of *** 7-day strategy produces the smallest RMSEs of 473 microarcseconds and 495 microarcseconds for the estimated X-and Y-component of pole coordinates,and 52 microseconds for length-of-day,***,the estimated geocenter motion is less affected by the arc length,even the shortest 1-day arc strategy can capture the seasonal variations of geocenter motion in Z *** scale estimation,extending the arc length notably improves the accuracy of the estimated station coordinates and scale,but this advantage becomes less noticeable in longer *** 7-day solution also obtains the closet scale results compared to ITRF2014,with the RMSE of 2.10×10^(–9).

关键词： Satellite laser ranging GNSS Geodetic parameters Earth rotation parameters Geocenter motion Terrestrial scale

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Modularized and Parametric Modeling Technology for Finite Element Simulations of Underground Engineering under Complicated Geological Conditions

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 621-645页

作者： jiaqi wu Li Zhuo Jianliang Pei Yao Li Hongqiang Xie Jiaming wu Huaizhong Liu State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China Research Institute of Testing and Inspection Sinohydro Bureau 7 Co.Ltd.Chengdu610213China

The surrounding geological conditions and supporting structures of underground engineering are often updated during construction,and these updates require repeated numerical *** improve the numerical modeling efficiency of underground engineering,a modularized and parametric modeling cloud server is developed by using Python *** basic framework of the cloud server is as follows:input the modeling parameters into the web platform,implement Rhino software and FLAC3D software to model and run simulations in the cloud server,and return the simulation results to the web *** modeling program can automatically generate instructions that can run the modeling process in Rhino based on the input modeling *** main modules of the modeling program include modeling the 3D geological structures,the underground engineering structures,and the supporting structures as well as meshing the geometric *** particular,various cross-sections of underground caverns are crafted as parametricmodules in themodeling *** and parametric modeling program is used for a finite element simulation of the underground powerhouse of the Shuangjiangkou Hydropower *** complicatedmodel is rapidly generated for the simulation,and the simulation results are ***,this modularized and parametric modeling program is applicable for three-dimensional finite element simulations and analyses.

关键词： Underground engineering modularized and parametric modeling finite element method complex geological structure cloud modeling

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Orbit and clock products for quad-system satellites with undifferenced ambiguity fixing approach

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Satellite Navigation 2024年第1期5卷 125-139页

作者： jiaqi wu Xingxing Li Yongqiang Yuan Keke Zhang Xin Li jiaqing Lou Yun Xiong School of Geodesy and Geomatics Wuhan University129 Luoyu RoadWuhan430079China Hubei Luojia Laboratory 129 Luoyu RoadWuhan430079China German Research Centre for Geosciences GFZ Telegrafenberg14473PotsdamGermany Technische Universitat Berlin(TUB) Straße Des 17.Juni10623BerlinGermany

Integer Ambiguity Resolution(IAR)can significantly improve the accuracy of GNSS Precise Orbit Determination(POD).Traditionally,the IAR in POD is achieved at the Double Differenced(DD)*** this contribution,we develop an Un-Differenced(UD)IAR method for Global Positioning System(GPS)+BeiDou Navigation Satellite System(BDS)+Galileo navigation satellite system(Galileo)+Global'naya Navigatsionnaya Sputnikovaya Sistema(GLONASS)quad-system POD by calibrating UD ambiguities in the raw carrier phase and generating the so-called carrier *** on this method,we generate the UD ambiguity-fixed orbit and clock products for the wuhan Innovation Application Center(IAC)of the International GNSS Monitoring and Assessment System(iGMAS).One-year observations in 2020 from 150 stations are employed to investigate performance of orbit and clock ***,the UD Ambiguity Resolution(AR)yields more resolved integer ambiguities than the traditional DD AR,scaling up to 9%,attributable to its avoidance of station baseline *** from the removal of ambiguity parameters,the computational efficiency of parameter estimation undergoes a substantial 70%*** with the float solution,the orbit consistencies of UD AR solution achieve the accuracy of 1.9,5.2,2.8,2.1,and 2.7 cm for GPS,BeiDou-2 Navigation Satellite System(BDS-2),BeiDou-3 Navigation Satellite System(BDS-3),Galileo,and GLONASS satellites respectively,reflecting enhancements of 40%,24%,54%,34%,and 42%.Moreover,the standard deviations of Satellite Laser Ranging(SLR)residuals are spanning 2.5–3.5 cm,underscoring a comparable accuracy to the DD AR solution,with discrepancies below 5%.A notable advantage of UD AR lies in its capability to produce the Integer Recovered Clock(IRC),facilitating Precise Point Positioning(PPP)AR without requiring additional Uncalibrated Phase Delay(UPD)*** assess the performance of quad-system kinematic PPP based on IRC,a network comprising 120 stations is uti

关键词： Multi-GNSS Precise orbit determination Integer recover clock Undifferenced ambiguity resolution iGMAS innovation application center

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The chemical characteristics of different sodium iron ethylenediaminetetraacetate sources and their relative bioavailabilities for broilers fed with a conventional corn‑soybean meal diet

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Journal of Animal Science and Biotechnology 2024年第2期15卷 826-843页

作者： Shengchen Wang Bingxin wu Ling Zhu Weiyun Zhang Liyang Zhang We wu jiaqi wu Yun Hu Tingting Li Xiaoyan Cui Xugang Luo College of Animal Science and Technology Yangzhou UniversityYangzhou 225000People’s Republic of China Mineral Nutrition Research Division State Key Laboratory of Animal NutritionInstitute of Animal ScienceChinese Academy of Agricultural SciencesBeijing 100193China

Background Our previous studies demonstrated that divalent organic iron(Fe)proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation(Qf)values displayed higher Fe bioavailabilities for *** iron ethylenediaminetetraacetate(NaFeEDTA)is a trivalent organic Fe source with the strongest chelating ligand ***,the bioavailability of Fe when administered as NaFeEDTA in broilers and other agricultural animals remains ***,the chemical characteristics of 12 NaFeEDTA products were *** these,one feed grade NaFeEDTA(Qf=2.07×10^(8)),one food grade NaFeEDTA(Qf=3.31×10^(8)),and one Fe proteinate with an extremely strong chelation strength(Fe-Prot ES,Qf value=8,590)were *** bioavailabilities relative to Fe sulfate(FeSO_(4)·7H_(2)O)for broilers fed with a conventional corn-soybean meal diet were evaluated during d 1 to 21 by investigating the effects of the above Fe sources and added Fe levels on the growth performance,hematological indices,Fe contents,activities and gene expressions of Fe-containing enzymes in various tissues of *** NaFeEDTA sources varied greatly in their chemical *** Fe concentration(PI),transferrin saturation(TS),liver Fe content,succinate dehydrogenase(SDH)activities in liver,heart,and kidney,catalase(CAT)activity in liver,and SDH mRNA expressions in liver and kidney increased linearly(P<0.05)with increasing levels of Fe ***,differences among Fe sources were detected(P<0.05)only for PI,liver Fe content,CAT activity in liver,SDH activities in heart and kidney,and SDH mRNA expressions in liver and *** on slope ratios from multiple linear regressions of the above indices on daily dietary analyzed Fe intake,the average bioavailabilities of Fe-Prot ES,feed grade NaFeEDTA,and food grade NaFeEDTA relative to the inorganic FeSO_(4)·7H_(2)O(100%)for broilers were 139%,155%,and 166%,***

关键词： Broilers Chelation strengths Fe-containing enzymes NaFeEDTA Relative bioavailabilities

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Impact of the Rapid Recovery Concept on Complications and Patient Quality of Life in the Perioperative Nursing of Robot-Assisted Radical Oesophageal Cancer

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Open Journal of Nursing 2024年第1期14卷 1-10页

作者： Rongrong Jiang Li Han Xiaoshan Ye jiaqi wu Jiahuan Weng Lihui Chen Chest Department Cancer Prevention and Treatment Center Sun Yat-sen University Guangzhou China

Aim: This study evaluates the impact of Enhanced Recovery After Surgery (ERAS) nursing on postoperative complications and quality of life in patients undergoing robot-assisted minimally invasive esophagectomy (RAMIE). Methods: A total of 150 patients who underwent RAMIE from January 2020 to January 2022 at our hospital were randomly assigned to either the observation group or the control group, with 75 patients in each. The control group received standard perioperative management and nursing care, while the observation group was treated with ERAS nursing strategies. Interventions continued until discharge, and outcomes such as postoperative complications, quality of life, and nutritional status were compared between the groups. Results: The observation group exhibited a significantly lower incidence of postoperative adverse reactions compared to the control group (P ionally, all dimension scores of the Short-Form 36 Health Survey (SF-36), including the total score, were higher in the observation group (P < 0.05). Furthermore, the Nutritional Risk Screening (NRS) scores for impaired nutritional status and disease severity, along with the total NRS score, were significantly lower in the observation group compared to the control group (P Conclusion: Implementing ERAS nursing in the perioperative care of patients undergoing RAMIE is associated with reduced postoperative complications and enhanced postoperative quality of life and nutritional status. .

关键词： Robot-Assisted Radical Esophageal Cancer Surgery Rapid Rehabilitation Surgical Nursing Perioperative Period Complications Quality of Life

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基于LMIENet图像增强的矿井下低光环境目标检测方法

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煤炭科学技术 2024年第5期52卷 222-235页

作者：田子建阳康吴佳奇陈伟中国矿业大学(北京)人工智能学院北京100083 煤矿智能化与机器人创新应急管理部重点实验室北京100083 中国矿业大学计算机科学与技术学院江苏徐州221116

煤矿井下工作环境复杂,存在人造光源亮度低、粉尘多和水气密度大等不利因素,导致现有的目标检测算法在应用到煤矿井下时,存在提取特征困难、目标识别和定位精度低等问题。提出一种煤矿井下低照度环境目标检测算法,由矿井低光图像增强模... 详细信息

煤矿井下工作环境复杂,存在人造光源亮度低、粉尘多和水气密度大等不利因素,导致现有的目标检测算法在应用到煤矿井下时,存在提取特征困难、目标识别和定位精度低等问题。提出一种煤矿井下低照度环境目标检测算法,由矿井低光图像增强模块LMIENet和目标检测模块组成,使用图像增强模块对原始图像进行画质提升,恢复各类图像信息,再使用目标检测网络对增强图像进行特定目标检测,有效提高检测的精确度。在图像增强模块中,改进Zero-DCE算法设计轻量级增强参数预测网络,计算像素级增强参数矩阵,用于低光照图像的亮度调整和画质增强,该网络通过设计的非参考损失函数隐性衡量图像的增强效果,引导网络进行无监督学习,使网络能够不依赖配对数据集对原始图像进行自适应的画质增强。目标检测模块中,采用YOLO v8n目标检测模型,其轻量化的模型尺寸和高灵活性可避免模型整体复杂度过高;采用Focal-EIoU Loss改进回归损失函数,有效加速模型收敛并提升模型检测精度。实验结果显示:与经典目标检测算法Faster R–CNN,SSD,RetinaNet,FCOS等相比,提出算法在自建矿井人员数据集上表现出色,低光照环境下目标检测的mAP@0.5达到98.0%,mAP@0.5∶0.95达64.8%,在实验环境中单帧图像推理时间仅11 ms,优于其他对比方法,证明提出算法能够有效实现在煤矿井下低照度复杂环境下的目标检测,且耗时短、计算效率高。

关键词：低照度矿井目标检测图像增强无监督学习

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从局部到全局的零参考低照度图像增强方法

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西安交通大学学报 2024年第4期58卷 158-169页

作者：杨伟王帅吴佳奇陈伟田子建中国矿业大学(北京)人工智能学院北京100083 国家矿山安全监察局内蒙古局呼和浩特010010 中国矿业大学计算机科学与技术学院江苏徐州221116

为解决现有的低照度图像增强方法存在的色彩失真、细节损失以及暗区增强不足和亮区增强过度导致低照度图像增强效果不理想的问题,提出了一种从局部到全局的零参考低照度图像增强方法。采用局部照度增强对低照度图像进行像素级增强,改进... 详细信息

为解决现有的低照度图像增强方法存在的色彩失真、细节损失以及暗区增强不足和亮区增强过度导致低照度图像增强效果不理想的问题,提出了一种从局部到全局的零参考低照度图像增强方法。采用局部照度增强对低照度图像进行像素级增强,改进了自适应光照映射估计函数,提升了照度调整能力,避免了生成大量的迭代参数,提高了模型的推理速度;采用基于Transformer结构的全局图像调整对局部增强后的图像进行全局调整,解决了亮区照度增强过度的曝光问题和暗区照度增强不足的问题,提升了图像的整体对比度;优化损失函数,对低照度图像特征和增强图像特征进行相似性约束,提升了目标检测精度。实验结果表明,LOL数据集上的客观指标峰值信噪比和结构相似性达到了20.18 dB和0.80,MIT-Adobe FiveK数据集上达到了23.31 dB和0.87,ExDark数据集上增强后图像的目标检测精度提高了7.6%,有效提升了低照度图像可视化质量和目标检测效果。

关键词：图像处理机器视觉轻量级网络低照度图像图像增强目标检测

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计及电动汽车的综合能源系统多主体协同低碳经济调度

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电力系统自动化 2024年第12期48卷 36-47页

作者：吴佳琦张谦黄耀宇吴小汉李春燕输变电装备技术全国重点实验室(重庆大学电气工程学院) 重庆市400044

针对未充分挖掘具有源荷双重特性的电动汽车集群调度潜力以辅助电力系统低碳运行的问题,提出了计及电动汽车的综合能源系统内多主体协同低碳经济调度策略。首先,考虑综合能源系统内多主体的电能交易构建了风电主体优化运行模型、计及碳... 详细信息

针对未充分挖掘具有源荷双重特性的电动汽车集群调度潜力以辅助电力系统低碳运行的问题,提出了计及电动汽车的综合能源系统内多主体协同低碳经济调度策略。首先,考虑综合能源系统内多主体的电能交易构建了风电主体优化运行模型、计及碳捕集与电转气系统综合灵活运行的电-热耦合系统优化运行模型以及电动汽车主体优化运行模型;其次,基于纳什谈判理论建立了综合能源系统内多主体合作运行模型,将其分解为多主体联盟效益最大化子问题和电能交易支付谈判子问题,并采用交替方向乘子法对上述两个子问题进行了分布式求解以保护各主体的隐私;最后,通过算例仿真验证了所提策略能够充分挖掘碳捕集-电转气系统和电动汽车集群支撑风电消纳实现综合能源系统碳减排的潜力,提高各主体的运行效益以及合作联盟的整体效益,有效实现综合能源系统内各主体协同互济,促进新能源消纳、提升系统低碳性和经济性。

关键词：低碳经济调度综合能源系统新能源消纳纳什谈判碳捕集电转气电动汽车

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进港航班滑入时间预测

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北京航空航天大学学报 2024年第7期50卷 2218-2224页

作者：唐小卫丁叶张生润任思豫吴佳琦南京航空航天大学民航学院南京211106

准确预测进港航班滑入时间对合理调配航班保障资源和提高机场场面运行效率具有重要意义,可有效克服各大机场粗放式预测航班进港时刻的不足,为此提出一种基于机器学习模型的滑入时间预测方法。以首都机场为具体研究对象,分析进港航班滑... 详细信息

准确预测进港航班滑入时间对合理调配航班保障资源和提高机场场面运行效率具有重要意义,可有效克服各大机场粗放式预测航班进港时刻的不足,为此提出一种基于机器学习模型的滑入时间预测方法。以首都机场为具体研究对象,分析进港航班滑入时间的影响因素并构建特征集;将线性回归、K-最近邻、支持向量机、决策树、随机森林和梯度提升回归树6种在滑出时间预测方面得到广泛应用的机器学习模型用于进港航班滑入时间预测。研究结果表明:在误差范围±3 min内6种机器学习模型的预测精度均超过90%,表明特征集的构建和模型的选择是有效的;综合预测性能与模型拟合评估结果,梯度提升回归树模型的预测效果最好;在梯度提升回归树模型上场面流量特征的贡献度最大,新引入的跨区特征对预测模型的贡献度超过了大部分传统特征。

关键词：航空运输机场场面运行滑行时间预测机器学习梯度提升回归树

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攻击性对恶意创造力的影响:有调节的中介模型

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心理科学 2024年第2期47卷 367-374页

作者：伍嘉麒任枭贡喆四川师范大学心理学院成都610066

本研究基于一般攻击模型和创造力四阶段理论,采用问卷法对553名大学生进行调查,考察愤怒反刍在攻击性与恶意创造力之间的中介作用以及意志控制的调节作用。研究结果表明:(1)攻击性显著正向预测恶意创造力;(2)愤怒反刍在攻击性与恶意创... 详细信息

本研究基于一般攻击模型和创造力四阶段理论,采用问卷法对553名大学生进行调查,考察愤怒反刍在攻击性与恶意创造力之间的中介作用以及意志控制的调节作用。研究结果表明:(1)攻击性显著正向预测恶意创造力;(2)愤怒反刍在攻击性与恶意创造力之间起部分中介作用;(3)意志控制正向调节愤怒反刍对恶意创造力的影响,具体而言,相对于低意志控制个体,该中介效应对高意志控制个体作用更大。

关键词：攻击性愤怒反刍意志控制恶意创造力

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