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Solubility and Thermodynamic Modeling of 3⁃Nitro⁃1,2,4⁃triazole⁃5⁃one(NTO)in Different Binary Solvents 被引量:1
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作者 GUO Hao-qi YANG Yu-lin 《含能材料》 北大核心 2025年第3期295-303,共9页
Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging f... Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging from 278.15 K to 318.15 K.The solubility in each system was found to be positively correlated with temperature.Furthermore,solubility data were analyzed using four equations:the modified Apelblat equation,Van’t Hoff equation,λh equation and CNIBS/R-K equations,and they provided satisfactory results for both two systems.The average root-mean-square deviation(105RMSD)values for these models were less than 13.93.Calculations utilizing the Van’t Hoff equation and Gibbs equations facilitated the derivation of apparent thermodynamic properties of NTO dissolution in the two systems,including values for Gibbs free energy,enthalpy and entropy.The%ζ_(H)is larger than%ζ_(TS),and all the%ζ_(H)data are≥58.63%,indicating that the enthalpy make a greater contribution than entropy to theΔG_(soln)^(Θ). 展开更多
关键词 3-nitro-l 2 4-triazole-5-one(NTO) SOLUBILITY thermodynamic models apparent thermodynamic analysis
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Teaching-Learning-Assessment Consistency of the 5E Teaching Model and Its Application of English Picture Book Teaching in Elementary School
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作者 HE Ai-jing YUAN Ling-na HUANG Lin-lin 《Journal of Literature and Art Studies》 2025年第7期580-586,共7页
The 5E model includes Engagement,Exploration,Explanation,Elaboration,and Evaluation,with“Evaluation”at the end,conflicting with teaching learning-evaluation consistency.Thus,formative levaluation is integrated into ... The 5E model includes Engagement,Exploration,Explanation,Elaboration,and Evaluation,with“Evaluation”at the end,conflicting with teaching learning-evaluation consistency.Thus,formative levaluation is integrated into the first four stages,and a summative evaluation table is designed for the fifth,enabling students to self-evaluate and reflect.Elementary school English picture book teaching is used as an example to demonstrate the optimized model's application. 展开更多
关键词 teaching and evaluation consistency 5E teaching model elementary English picture book teaching
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A Laboratorial Testing Scheme for 5G System:Channel Model Principle and Field Experiment Validation
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作者 Zhang Yuxiang Zhang Jianhua +7 位作者 Kang Yanan Zhao Mengxuan Qi Pan Zhang Zhen Tang Pan Tian Lei Liu Guangyi Yao Yuan 《China Communications》 2025年第9期113-128,共16页
As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple ... As the commercialization of the fifth gen-eration communication(5G)is sped up,its system testing scheme is vital for the successful deployment of 5G.Especially,5G relies on the scale-increased multiple-input-multiple output(MIMO)technique to improve its capacity and coverage.Thus,testing new functions of the 5G MIMO system accurately and ef-ficiently,including beamforming(beam-tracking with movement)and multiple-user(MU)multiplexing,is a challenging task.This paper tries to construct a lab-oratorial hardware and conduct equipment-controlled field testing.Firstly,the testing scheme is presented,which is composed of the framework,the channel models and the validation methods.Then,the channel model principles are explained in detail due to its di-rect influence on the testing accuracy.Specifically,we utilize the spatial consistency and the multi-link cor-relation properties to emulate the high-speed dynamic time-varying(HDT)and the multiple-cell(MC)-MU-MIMO channels.Finally,the above testing scheme is verified in a Shanghai 5G field experiment with the practical commercial equipment and the channel em-ulator.The results show that the 5G new functions are tested accurately and efficiently by switching the channel emulation configurations. 展开更多
关键词 channel model field experiment high-speed dynamic time-varying(HDT) multiple-cell-multiple-user-multiple-input-multiple-output(MC-MU-MIMO) testing scheme the fifth generation communication(5G)
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“Water”accelerated B(C_(6)F_(5))_(3)-catalyzed Mukaiyama-aldol reaction:Outer-sphere activation model
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作者 Zhenguo Zhang Lanyang Li +6 位作者 Xinlong Zong Yongheng Lv Shuanglei Liu Liang Ji Xuefei Zhao Zhenhua Jia Teck-Peng Loh 《Chinese Chemical Letters》 2025年第7期334-339,共6页
A“water”accelerated metal-free catalytic system has been discovered for the Mukaiyama-aldol reaction.The system involves the use of B(C_(6)F_(5))_(3) as a catalyst,which is water-tolerant and able to activate the ca... A“water”accelerated metal-free catalytic system has been discovered for the Mukaiyama-aldol reaction.The system involves the use of B(C_(6)F_(5))_(3) as a catalyst,which is water-tolerant and able to activate the carbonyl group through a hydrogen bonding network generated by the catalyst.This activation method allows the reactions to be performed with very low catalyst loading,as low as 0.5 mol%.The scope of substrates is broad and a wide variety of functional groups are well tolerated.Diverse aliphatic aldehydes,aromatic aldehydes,unsaturated aldehydes and aromatic ketones coupled with silyl enol ethers/silyl ketone acetals to generate their correspondingβ-hydroxy carbonyl compounds in moderate to good yields.This discovery represents a significant advancement in the field of organic synthesis,as it provides a new,practical and sustainable solution for carbon-carbon bond formation in water. 展开更多
关键词 B(C_(6)F_(5))_(3)-catalysis Hydrogen bonding network Water-acceleration Mukaiyama-aldol reaction Outer-sphere activation model
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青岛大学临床医学“5+3”一体化专业人才培养模式改革与实践
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作者 王晶 王建勋 +2 位作者 王飞 李冰 任贺 《青岛大学学报(医学版)》 2025年第2期297-300,共4页
目的探索临床医学“5+3”一体化专业人才培养模式,以培养兼具拔尖临床实践水平和科研创新能力的高层次医学人才。方法以青岛大学2015—2023级临床医学“5+3”一体化专业学生为研究对象,在人才培养过程中针对课程体系、制度保障体系、教... 目的探索临床医学“5+3”一体化专业人才培养模式,以培养兼具拔尖临床实践水平和科研创新能力的高层次医学人才。方法以青岛大学2015—2023级临床医学“5+3”一体化专业学生为研究对象,在人才培养过程中针对课程体系、制度保障体系、教学评价、科研能力创新、临床技能提升等方面进行改革和实践。结果经10年探索,形成了具有青岛大学医学特色的“四层三阶”临床医学“5+3”一体化专业人才培养模式,其中四层为“目标导向-平台支撑-导师引领-政策激励”四层次培养路径,三阶为“2.5+2.5+3.0”三阶段递进式培养模式。结论通过临床医学“5+3”一体化专业人才培养模式改革,提升了学生的科研创新和临床能力,教学效果显著,产生了广泛的社会影响,有利于实现“卓越医师+临床科学家”的人才培养目标。 展开更多
关键词 临床医学 5+3”一体化 培养模式 教育 医学
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Hexagon-Islands Density and Size Distribution on Growing Single-Walled Carbon Nanotubes in the Kinetic 5-Vertex Model
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作者 Sènan Ida Valérie Hontinfinde Josaphat Adda +2 位作者 Joel Kple Franck Zounmenou Félix Hontinfinde 《World Journal of Condensed Matter Physics》 CAS 2024年第4期77-95,共19页
A kinetic 5-vertex model is used to investigate hexagon-islands formation on growing single-walled carbon nanotubes (SWCNT). In the model, carbon atoms adsorption and migration processes on the SWCNT edge are consider... A kinetic 5-vertex model is used to investigate hexagon-islands formation on growing single-walled carbon nanotubes (SWCNT). In the model, carbon atoms adsorption and migration processes on the SWCNT edge are considered. These two dynamic processes are assumed to be mutually independent as well as mutually dependent as far as the whole growth of the nanotube is concerned. Key physical parameters of the model are the growth time t, the diffusion length Γ defined as the ratio of the diffusion rate D to the carbon atomic flux F and the SWCNT chiral angle. The kinetic equation that describes the nanotube edge dynamics is solved using kinetic Monte Carlo simulations with the Bortz, Kalos and Lebowitz update algorithm. The behaviors of islands density and size distribution are investigated within the growth parameters’ space. Our study revealed key mechanisms that enable the formation of a new ring of hexagons at the SWCNT edge. The growth occurs either by pre-existing steps propagation or by hexagon-islands growth and coalescence on terraces located between dislocation steps, depending on values of model parameters. This should offer a road map for edge design in nanotubes production. We also found that in appropriate growth conditions, the islands density follows Gaussian and generalized Wigner distributions whereas their size distribution at a given growth time shows a decreasing exponential trend. 展开更多
关键词 Kinetic 5-Vertex model Single-Walled Carbon Nanotube Monte Carlo Simulations Island Density and Size Distribution Gaussian and Wigner Distributions
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Benchmarking YOLOv5 models for improved human detection in search and rescue missions
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作者 Namat Bachir Qurban Ali Memon 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第1期70-80,共11页
Drone or unmanned aerial vehicle(UAV)technology has undergone significant changes.The technology allows UAV to carry out a wide range of tasks with an increasing level of sophistication,since drones can cover a large ... Drone or unmanned aerial vehicle(UAV)technology has undergone significant changes.The technology allows UAV to carry out a wide range of tasks with an increasing level of sophistication,since drones can cover a large area with cameras.Meanwhile,the increasing number of computer vision applications utilizing deep learning provides a unique insight into such applications.The primary target in UAV-based detection applications is humans,yet aerial recordings are not included in the massive datasets used to train object detectors,which makes it necessary to gather the model data from such platforms.You only look once(YOLO)version 4,RetinaNet,faster region-based convolutional neural network(R-CNN),and cascade R-CNN are several well-known detectors that have been studied in the past using a variety of datasets to replicate rescue scenes.Here,we used the search and rescue(SAR)dataset to train the you only look once version 5(YOLOv5)algorithm to validate its speed,accuracy,and low false detection rate.In comparison to YOLOv4 and R-CNN,the highest mean average accuracy of 96.9%is obtained by YOLOv5.For comparison,experimental findings utilizing the SAR and the human rescue imaging database on land(HERIDAL)datasets are presented.The results show that the YOLOv5-based approach is the most successful human detection model for SAR missions. 展开更多
关键词 Unmanned aerial vehicle(UAV) Search and rescue(SAR) You look only once(YOLO)model You only look once version 5 (YOLOv5)
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沸石间转化法制备xNi@HZSM-5用于煤焦油催化提质的研究
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作者 郭向阳 樊磊 +3 位作者 王明义 董子豪 王玉高 王俊文 《煤炭转化》 北大核心 2025年第6期17-26,共10页
煤热解焦油催化提质可以将其中的重质组分转化为轻质芳烃,但负载型Ni/HZSM-5中金属Ni多位于分子筛的外表面,在提升轻质芳烃含量的同时会造成焦油过度裂解。采用以HBeta为母体的沸石间转化法制备x Ni@HZSM-5(x为Ni的质量分数,x=3,5,7),... 煤热解焦油催化提质可以将其中的重质组分转化为轻质芳烃,但负载型Ni/HZSM-5中金属Ni多位于分子筛的外表面,在提升轻质芳烃含量的同时会造成焦油过度裂解。采用以HBeta为母体的沸石间转化法制备x Ni@HZSM-5(x为Ni的质量分数,x=3,5,7),将金属Ni封装于分子筛的孔道内,利用HZSM-5分子筛孔道的空间限域特性实现富氢气体活化和焦油裂解活性位点的分离;同时,考察了H2气氛下xNi@HZSM-5对焦油模型化合物芘和荧蒽催化性能及加氢产物的影响。结果表明:经沸石间转化法制备的5Ni@HZSM-5中分子筛晶体呈现非常均匀规则的米粒状颗粒,且金属Ni具有较高的分散性;在原位催化裂解过程中,沸石间转化前后催化剂载体的改变对焦油各性质影响不大,且转化后的催化剂焦油产率、轻质焦油产率及含量均明显高于其母体沸石。其中,5Ni@HZSM-5具有最大的芘和荧蒽转化率,分别为49.1%和56.8%,此时轻质芳烃选择性也达到最大,分别为70.3%和76.0%。 展开更多
关键词 焦油催化提质 沸石间转化法 xNi@HZSM-5 模型化合物 轻质芳烃
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基于GF-5高光谱影像的滇中高原灌区土壤有机碳含量反演研究
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作者 严正飞 杨明龙 +3 位作者 唐秀娟 夏永华 杨赈 李万涛 《南方农业学报》 北大核心 2025年第1期124-134,共11页
【目的】基于GF-5高光谱影像构建针对滇中高原灌区土壤有机碳(SOC)含量反演模型,为后续开展滇中高原灌区SOC含量反演研究提供参考依据。【方法】选取云南省楚雄州姚安县为研究区,以GF-5高光谱影像为基础数据源,筛选出与SOC含量相关性较... 【目的】基于GF-5高光谱影像构建针对滇中高原灌区土壤有机碳(SOC)含量反演模型,为后续开展滇中高原灌区SOC含量反演研究提供参考依据。【方法】选取云南省楚雄州姚安县为研究区,以GF-5高光谱影像为基础数据源,筛选出与SOC含量相关性较高的预处理方法并构建光谱指数,基于连续投影算法(SPA)和竞争性自适应重加权算法(CARS)筛选特征波段组合,以筛选的特征波段、光谱指数、地形因子及Sentinel-1后向散射系数为辅助变量进行组合,结合实地采样的SOC含量数据,运用XGBoost模型进行SOC含量反演。【结果】在21种数据预处理方法中以AM-Normalize的预处理效果最优,与实测SOC含量的相关系数为0.7544;其次是SG-FD、SD和FD的预处理效果,与实测SOC含量的相关系数分别为0.6791、0.6671和0.6202。SPA筛选的波段反演效果最优,其决定系数(R^(2))较CARS和全波段数据分别提升了0.0739和0.1524,均方根误差(RMSE)分别降低了0.9279和1.2793。引入地形因子的变量模型G2,其R^(2)较变量模型G1(特征波段+光谱指数)提升了0.0398,RMSE降低了0.1685;进一步加入Sentinel-1后向散射系数,变量模型G3的R^(2)较变量模型G2提升了0.0255,RMSE降低了0.1385。基于GF-5高光谱影像的SOC含量反演结果显示,滇中高原姚安灌区的SOC含量范围为9.8443~29.2514 g/kg,平均为19.4447 g/kg,与土壤样本SOC含量实测值的范围(10.47~30.11 g/kg)及平均值(20.6307 g/kg)较接近。【结论】基于GF-5高光谱影像构建的XGBoost模型,经AM-Normalize预处理降低噪声干扰、SPA筛选特征波段及引入光谱指数、地形因子和Sentinel-1后向散射系数后,能有效提升SOC含量反演的精度和适用性,为滇中高原地区SOC含量预测提供技术支撑。 展开更多
关键词 土壤有机碳(SOC) GF-5高光谱影像 光谱指数 XGBoost模型 滇中高原
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The construction and practice of humanistic care teaching model based on 5C care theory
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作者 Xi-Peng liu Qing-Qing Li +3 位作者 Yu-Zi Zhong Fei-Fei Hong Yan Li Yi-Jing Wang 《Nursing Communications》 2024年第8期1-9,共9页
Objective:To construct a scientific and feasible teaching mode based on 5C caring theory and evaluate it,so as to provide a reference basis for future study about nursing humanistic quality education.Methods:Based on ... Objective:To construct a scientific and feasible teaching mode based on 5C caring theory and evaluate it,so as to provide a reference basis for future study about nursing humanistic quality education.Methods:Based on the 5C caring theory,the teaching design and teaching content were revising and implementing in the intervention group.Before and after the implementation of the course,a questionnaire survey was conducted using the Caring Ability Inventory(CAI).The results of the surveys were collected,and the data were statistically analysis using SPSS.Results:After the implementation of the course,the cognitive dimension,patience dimension,and humanistic caring ability scores of the nursing students in the intervention group improved compared with those before the implementation of the course(P<0.05).There were no significant difference in the control group(P>0.05).Conclusion:The humanistic caring teaching model based on 5C caring theory has a positive effect on improving nursing students'humanistic caring ability.In the future nursing teaching,the modules with the characteristics of humanistic caring ability can be increased,and carry out the educational reform throughout the humanistic caring ability.Actively guiding nursing students to establish the awareness of humanistic caring,so as to lay a solid foundation for high-quality clinical nursing work. 展开更多
关键词 5C caring theory humanistic caring ability undergraduate nursing students teaching model
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Modeling and Comprehensive Review of Signaling Storms in 3GPP-Based Mobile Broadband Networks:Causes,Solutions,and Countermeasures
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作者 Muhammad Qasim Khan Fazal Malik +1 位作者 Fahad Alturise Noor Rahman 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期123-153,共31页
Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important a... Control signaling is mandatory for the operation and management of all types of communication networks,including the Third Generation Partnership Project(3GPP)mobile broadband networks.However,they consume important and scarce network resources such as bandwidth and processing power.There have been several reports of these control signaling turning into signaling storms halting network operations and causing the respective Telecom companies big financial losses.This paper draws its motivation from such real network disaster incidents attributed to signaling storms.In this paper,we present a thorough survey of the causes,of the signaling storm problems in 3GPP-based mobile broadband networks and discuss in detail their possible solutions and countermeasures.We provide relevant analytical models to help quantify the effect of the potential causes and benefits of their corresponding solutions.Another important contribution of this paper is the comparison of the possible causes and solutions/countermeasures,concerning their effect on several important network aspects such as architecture,additional signaling,fidelity,etc.,in the form of a table.This paper presents an update and an extension of our earlier conference publication.To our knowledge,no similar survey study exists on the subject. 展开更多
关键词 Signaling storm problems control signaling load analytical modeling 3GPP networks smart devices diameter signaling mobile broadband data access data traffic mobility management signaling network architecture 5G mobile communication
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A multi-dimensional trust attestation solution in 5G-IoT
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作者 Xiangrong Li Yu Zhang +2 位作者 Haotian Zhu Yubo Wang Junjia Huang 《Digital Communications and Networks》 2025年第1期225-233,共9页
The core missions of IoT are to sense data,transmit data and give feedback to the real world based on the calculation of the sensed data.The trust of sensing source data and transmission network is extremely important... The core missions of IoT are to sense data,transmit data and give feedback to the real world based on the calculation of the sensed data.The trust of sensing source data and transmission network is extremely important to IoT security.5G-IoT with its low latency,wide connectivity and high-speed transmission extends the business scenarios of IoT,yet it also brings new challenges to trust proof solutions of IoT.Currently,there is a lack of efficient and reliable trust proof solutions for massive dynamically connected nodes,while the existing solutions have high computational complexity and can't adapt to time-sensitive services in 5G-IoT scenarios.In order to solve the above problems,this paper proposes an adaptive multi-dimensional trust proof solution.Firstly,the static and dynamic attributes of sensing nodes are metricized,and the historical interaction as well as the recommendation information are combined with the comprehensive metric of sensing nodes,and a multi-dimensional fine-grained trusted metric model is established in this paper.Then,based on the comprehensive metrics,the sensing nodes are logically grouped and assigned with service levels to achieve the screening and isolation of malicious nodes.At the same time,the proposed solution reduces the energy consumption of the metric process and optimizes the impact of real-time metrics on the interaction latency.Simulation experiments show that the solution can accurately and efficiently identify malicious nodes and effectively guarantee the safe and trustworthy operation of 5G-IoT nodes,while having a small impact on the latency of the 5G network. 展开更多
关键词 5G-IoT Trusted metrics Trust model
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Prediction models for scour depth around circular compound bridge piers
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作者 Siva Krishna Reddy Venu Chandra 《Water Science and Engineering》 2025年第3期378-390,共13页
Scour around bridge pier foundations is a complex phenomenon that can threaten structural stability.Accurate prediction of scour depth around compound piers remains challenging for bridge engineers.This study investig... Scour around bridge pier foundations is a complex phenomenon that can threaten structural stability.Accurate prediction of scour depth around compound piers remains challenging for bridge engineers.This study investigated the effect of foundation elevation on scour around compound piers and developed reliable scour depth prediction models for economical foundation design.Experiments were conducted under clear-water conditions using two circular piers:(1)a uniform pier(with a diameter of D)and(2)a compound pier consisting of a uniform pier resting on a circular foundation(with a foundation diameter(D_(f))of 2D)positioned at various elevations(Z)relative to the channel bed.Results showed that foundation elevation significantly affected scour depth.Foundations at or below the bed(Z/D≥0)reduced scour,while those projecting into the flow field(Z/D<0)increased scour.The optimal foundation elevation was found to be 0.1D below the bed level,yielding a 57%reduction in scour depth compared to the uniform pier due to its shielding effect against downflow and horseshoe vortices.In addition,regression,artificial neural network(ANN),and M5 model tree models were developed using experimental data from this and previous studies.The M5 model outperformed the traditional HEC-18 equation,regression,and ANN models,with a coefficient of determination greater than 0.85.Sensitivity analysis indicated that flow depth,foundation elevation,and diameter significantly influenced scour depth prediction,whereas sediment size had a lesser impact. 展开更多
关键词 Local scour Uniform piers Compound piers Scour depth prediction ANN M5 model
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无人机倾斜摄影测量技术的5镜头与2镜头建模分析
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作者 向松林 《绿色科技》 2025年第14期220-223,278,共5页
针对实景三维建模中如何实现快捷、适用的问题,从无人机倾斜摄影测量技术建模的角度出发,采用大疆m^(3)00获取5镜头的倾斜影像,分别选取5个镜头的影像和其中2个镜头的影像,通过采用ContextCaptureCenter软件进行实景三维建模,对比分析5... 针对实景三维建模中如何实现快捷、适用的问题,从无人机倾斜摄影测量技术建模的角度出发,采用大疆m^(3)00获取5镜头的倾斜影像,分别选取5个镜头的影像和其中2个镜头的影像,通过采用ContextCaptureCenter软件进行实景三维建模,对比分析5个镜头与其中2个镜头三维建模的效果与精度。经过实验对比分析,总结了不同影像组合生产三维模型的优缺点,结果表明:在应用倾斜摄影测量技术生产作业时,可根据项目任务紧急程度、应用需求等不同侧重点,选取5镜头或2镜头影像进行生产作业,可以做到倾斜摄影测量技术准确满足不同应用场景。 展开更多
关键词 无人机 倾斜摄影 三维建模 5镜头 2镜头
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基于MPPG 5.a的国产TAICHI加速器TPS模型验收与调试
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作者 汪之群 雷琪琪 +4 位作者 王涛 庞廷田 祝鹤龄 邱杰 杨波 《中国医疗设备》 2025年第7期40-48,共9页
目的验证国产TAICHI设备在RayStation放疗计划系统中建立的束流模型剂量计算的准确度,使设备可以更好地服务于临床患者治疗。方法以美国医学物理协会发布的MPPG 5.a和TG119报告为依据,对TAICHI设备的模型剂量计算模型进行验证,包括PDD... 目的验证国产TAICHI设备在RayStation放疗计划系统中建立的束流模型剂量计算的准确度,使设备可以更好地服务于临床患者治疗。方法以美国医学物理协会发布的MPPG 5.a和TG119报告为依据,对TAICHI设备的模型剂量计算模型进行验证,包括PDD曲线、Profile曲线、TG119、临床病案验证等。结果不同源皮距基础野2 mm/2%伽玛通过率在浅深度(0~20 cm)结果基本都接近100%,深深度(水下25 cm)结果相比于浅深度较差,但均值仍在93%以上,所有点剂量偏差结果均小于2%(小野修正后),因此模型中束流跟设备实际输出基本一致;针对TG119测试病例,调强放疗(Intensity Modulated Radiation Therapy,IMRT)和容积旋转调强放疗(Volumetric Modulated Arc Therapy,VMAT)点剂量及面剂量伽玛通过率结果均满足且远优于TG119报告要求的标准;IMRT和VMAT临床患者计划点剂量验证偏差结果平均值分别为0.48%和0.47%,面剂量测试2 mm/2%及3 mm/3%伽玛通过率分别为95.58%、99.46%和96.75%、99.30%,结果均满足临床需求;IMRT和VMAT肺部端到端测试结果通过,其点剂量偏差分别为-0.495%和-2.602%。结论国产TAICHI经过MPPG 5.a和TG119系统验证后,结果满足并远优于报告要求标准,符合临床要求,可用于优化临床患者治疗计划,对于深深度拟合不好的情况,后续建模过程中需多关注。 展开更多
关键词 TAICHI加速器 TPS模型调试 MPPG 5.a TG119 国产加速器 调强放疗(IMRT) 容积旋转调强放疗(VMAT)
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基于增强LetNet-5的非霍奇金淋巴瘤辅助诊断 被引量:6
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作者 张剑飞 崔文升 +1 位作者 王真 杜晓昕 《科学技术与工程》 北大核心 2020年第16期6527-6531,共5页
针对主流网络模型在医学辅助诊断适用性低的问题,在现有LetNet-5模型的基础上,给出了增强LetNet-5模型用于非霍奇金淋巴瘤的智能辅助诊断方案。首先将获取到的数据集进行图像切分和归一化等预处理操作,然后使用深度学习框架KERAS搭建增... 针对主流网络模型在医学辅助诊断适用性低的问题,在现有LetNet-5模型的基础上,给出了增强LetNet-5模型用于非霍奇金淋巴瘤的智能辅助诊断方案。首先将获取到的数据集进行图像切分和归一化等预处理操作,然后使用深度学习框架KERAS搭建增强前后的LetNet-5模型,接着对增强前后的网络模型进行训练、预测和评估,最后对模型的泛化能力和稳定性进行验证。实验表明,增强LetNet-5模型相对于原始LetNet-5模型具有更高的识别精度、更好的稳定性和更快的模型收敛速度,为非霍奇金淋巴瘤的诊断提供科学性的指导并具有重要的临床价值。 展开更多
关键词 深度学习 卷积神经网络 letnet-5模型 计算机辅助诊断
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Arrhenius-type constitutive model and dynamic recrystallization behavior of V-5Cr-5Ti alloy during hot compression 被引量:10
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作者 李鱼飞 王震宏 +2 位作者 张林英 罗超 赖新春 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期1889-1900,共12页
To clarify the high temperature flow stress behavior and microstructures evolution of a V-5Cr-5Ti (mass fraction, %) alloy, the isothermal hot compression tests were conducted in the temperature range of 1423-1573 K... To clarify the high temperature flow stress behavior and microstructures evolution of a V-5Cr-5Ti (mass fraction, %) alloy, the isothermal hot compression tests were conducted in the temperature range of 1423-1573 K with strain rates of 0.01, 0.1, and 1 s-1. The results show that the measured flow stress should be revised by friction and the calculated values of friction coefficient m are in the range of 0.45-0.56. Arrhenius-type constitutive equation was developed by regression analysis. The comparison between the experimental and predicted flow stress shows that the R~ and the average absolute relative error (AARE) are 0.948 and 5.44%, respectively. The measured apparent activation energy Qa is in the range of 540-890 kJ/mol. Both dis-continuous dynamic recrystallization (DDRX) and continuous dynamic recrystallization (CDRX) mechanisms are observed in the deformed alloy, but dynamic recovery (DRV) is the dominant softening mechanism up to a true strain of 1.5. 展开更多
关键词 V-5Cr-5Ti alloy constitutive model flow stress dynamic recrystallization
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SLC6A9对结直肠癌细胞生长和对5-FU药物敏感性的影响 被引量:1
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作者 张岩 田素礼 +1 位作者 周勇旭 刘昶 《现代肿瘤医学》 CAS 2024年第7期1236-1241,共6页
目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结... 目的:研究溶质载体家族6成员9(solute carrier family 6 member 9,SLC6A9)表达对结直肠癌细胞增殖、迁移和5-氟尿嘧啶(5-fluorouracil,5-FU)药物敏感性的影响。方法:TCGA数据库分析、实时荧光定量PCR和Western blot分析检测SLC6A9在结肠癌组织、正常结肠细胞系(NCM460)和结直肠癌细胞系(SW620、HCT116、HT29、Lovo和SW480)中的表达。将SCL6A9过表达质粒及阴性对照(SLC6A9 OE、Vector)转染HT29细胞,将SCL6A9小干扰RNA及阴性对照(SLC6A9 siRNA1#、siRNA2#和Scramble)转染SW620细胞。划痕愈合实验和Transwell实验检测各组细胞的迁移、侵袭能力。Western blot和细胞免疫荧光检测EMT相关蛋白E-cadherin、Vimentin的表达水平。利用CCK-8法和构建裸鼠移植瘤模型检测SLC6A9过表达对结直肠癌细胞5-FU药物敏感性的影响。结果:与正常结肠组织和NCM460细胞相比,SLC6A9在结肠癌组织和结直肠癌细胞系中低表达(均P<0.05)。SLC6A9过表达引起E-cadherin蛋白表达增加,Vimentin蛋白水平降低,抑制结直肠癌细胞的迁移、侵袭(P<0.05)。SLC6A9低表达引起E-cadherin蛋白表达降低,Vimentin蛋白水平增加,促进结直肠癌细胞的迁移、侵袭能力(P<0.05)。SLC6A9过表达提高了5-FU的药物敏感性,并使肿瘤生长缓慢,质量减轻(P<0.05)。而SLC6A9低表达降低了5-FU的药物敏感性(P<0.05)。结论:SLC6A9过表达能够抑制结直肠癌细胞的迁移、侵袭和EMT进程,并增强5-FU对结直肠癌细胞的药物敏感性。 展开更多
关键词 结肠肿瘤 SLC6A9 细胞迁移和侵袭分析 EMT 5-FU 异种移植模型实验
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Systematic Geometric Error Modeling for Workspace Volumetric Calibration of a 5-axis Turbine Blade Grinding Machine 被引量:30
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作者 Abdul Wahid Khan 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第5期604-615,共12页
A systematic geometric model has been presented for calibration of a newly designed 5-axis turbine blade grinding machine. This machine is designed to serve a specific purpose to attain high accuracy and high efficien... A systematic geometric model has been presented for calibration of a newly designed 5-axis turbine blade grinding machine. This machine is designed to serve a specific purpose to attain high accuracy and high efficiency grinding of turbine blades by eliminating the hand grinding process. Although its topology is RPPPR (P: prismatic; R: rotary), its design is quite distinct from the competitive machine tools. As error quantification is the only way to investigate, maintain and improve its accuracy, calibra- tion is recommended for its performance assessment and acceptance testing. Systematic geometric error modeling technique is implemented and 52 position dependent and position independent errors are identified while considering the machine as five rigid bodies by eliminating the set-up errors of workpiece and cutting tool. 39 of them are found to have influential errors and are accommodated for finding the resultant effect between the cutting tool and the workpiece in workspace volume. Rigid body kinematics techniques and homogenous transformation matrices are used for error synthesis. 展开更多
关键词 5-axis machine tools CALIBRATION modeling geometric errors kinematics homogenous transformation matrices
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A Heavy Sea Fog Event over the Yellow Sea in March 2005: Analysis and Numerical Modeling 被引量:81
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作者 高山红 林行 +1 位作者 沈飙 傅刚 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2007年第1期65-81,共17页
In this paper, a heavy sea fog episode that occurred over the Yellow Sea on 9 March 2005 is investigated. The sea fog patch, with a spatial scale of several hundred kilometers at its mature stage, reduced visibility a... In this paper, a heavy sea fog episode that occurred over the Yellow Sea on 9 March 2005 is investigated. The sea fog patch, with a spatial scale of several hundred kilometers at its mature stage, reduced visibility along the Shandong Peninsula coast to 100 m or much less at some sites. Satellite images, surface observations and soundings at islands and coasts, and analyses from the Japan Meteorology Agency (JMA) axe used to describe and analyze this event. The analysis indicates that this sea fog can be categorized as advection cooling fog. The main features of this sea fog including fog area and its movement axe reasonably reproduced by the Fifth-generation Pennsylvania State University/National Center for Atmospheric Research Mesoscale Model (MM5). Model results suggest that the formation and evolution of this event can be outlined as: (1) southerly warm/moist advection of low-level air resulted in a strong sea-surface-based inversion with a thickness of about 600 m; (2) when the inversion moved from the warmer East Sea to the colder Yellow Sea, a thermal internal boundary layer (TIBL) gradually formed at the base of the inversion while the sea fog grew in response to cooling and moistening by turbulence mixing; (3) the sea fog developed as the TIBL moved northward and (4) strong northerly cold and dry wind destroyed the TIBL and dissipated the sea fog. The principal findings of this study axe that sea fog forms in response to relatively persistent southerly waxm/moist wind and a cold sea surface, and that turbulence mixing by wind shear is the primary mechanism for the cooling and moistening the marine layer. In addition, the study of sensitivity experiments indicates that deterministic numerical modeling offers a promising approach to the prediction of sea fog over the Yellow Sea but it may be more efficient to consider ensemble numerical modeling because of the extreme sensitivity to model input. 展开更多
关键词 sea fog Yellow Sea numerical modeling MM5 sensitivity experiments
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