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基于UPLC-Q-TOF MS技术结合UNIFI软件快速筛查中药中非法添加调节性功能化合物
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作者 廖敏 王影超 +2 位作者 陈琪 姜莲 王海宁 《质谱学报》 北大核心 2025年第3期370-379,共10页
本研究采用超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF MS)技术结合UNIFI软件,建立了一种快速、准确检测中药中非法添加调节性功能化合物的方法。根据中药剂型的不同选择相应的样品制备方法,使用ACQUITY UPLC HSS T3色谱柱(2.1 mm&#... 本研究采用超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF MS)技术结合UNIFI软件,建立了一种快速、准确检测中药中非法添加调节性功能化合物的方法。根据中药剂型的不同选择相应的样品制备方法,使用ACQUITY UPLC HSS T3色谱柱(2.1 mm×100 mm,1.8μm),以乙腈-0.1%甲酸溶液为流动相进行梯度洗脱;在电喷雾离子源正离子模式下,使用MS^(E)模式采集数据。通过UNIFI软件建立靶向筛查数据库,并参考欧盟SANTE/11312/2021指南设定筛查条件,实现检测结果的自动化筛查。结果表明,本方法能够在12 min内快速筛查31种目标化合物,检出限为0.25~15.00 mg/kg(或mg/L)。在对20批次补肾壮阳类中药样品的检测中发现,7批次样品存在非法添加,其中4批次样品检出标准检测方法以外的化合物。该方法具有快速、准确、覆盖范围广且可灵活扩展的优点,可为中药中非法添加物的监管提供技术支持。 展开更多
关键词 超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF MS) unifi软件 中药 非法添加 调节性功能化合物 快速筛查
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基于UPLC-Q-TOF-MS/MS结合UNIFI的珠子参皂苷类化学成分分析及多指标含量测定 被引量:1
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作者 张苡嘉 杨婧潇 +4 位作者 胡新悦 黄嘉诚 王炜 刘乐平 严建业 《天然产物研究与开发》 北大核心 2025年第5期904-917,共14页
对珠子参中皂苷类成分进行定性鉴别分析,建立珠子参皂苷类多成分含量测定方法。采用超高效液相色谱-飞行时间质谱(UPLC-Q-TOF-MS/MS)技术对珠子参进行正、负离子模式扫描,使用UNIFI天然产物信息平台对珠子参所含的化学成分进行定性鉴别... 对珠子参中皂苷类成分进行定性鉴别分析,建立珠子参皂苷类多成分含量测定方法。采用超高效液相色谱-飞行时间质谱(UPLC-Q-TOF-MS/MS)技术对珠子参进行正、负离子模式扫描,使用UNIFI天然产物信息平台对珠子参所含的化学成分进行定性鉴别分析;以0.1%磷酸水-乙腈溶液为流动相进行梯度洗脱,柱温30℃,流速0.3 mL/min,进行珠子参皂苷类多成分含量测定。珠子参中共鉴定出39个化学成分,包括37个皂苷类化合物和2个皂苷母核,并总结了皂苷类化合物的裂解规律,建立了UPLC同时测定珠子参中人参皂苷Rb1、人参皂苷Ro、人参皂苷Rb3、竹节参皂苷IV、竹节参皂苷IVa、人参皂苷Rd、姜状三七皂苷R1和金盏花苷E的多指标含量测定方法,该方法中8个待测成分在检测质量浓度范围内线性关系良好,精密度、重复性、稳定性的相对标准偏差(relative standard deviation,RSD)均小于3.0%,样品中人参皂苷Rb1、人参皂苷Ro、人参皂苷Rb3、竹节参皂苷IV、竹节参皂苷IVa、人参皂苷Rd、姜状三七皂苷R1和金盏花苷E的平均加样回收率分别为102.4%、103.1%、97.97%、99.42%、102.7%、102.1%、95.23%、100.5%,RSD分别为1.0%、0.98%、0.81%、2.3%、0.81%、1.9%、0.96%、1.8%。该研究建立的方法可快速、准确地对珠子参中的皂苷类成分进行定性及定量分析。 展开更多
关键词 珠子参 UPLC-Q-TOF-MS/MS unifi 成分分析 含量测定
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超高效液相色谱-四极杆-飞行时间高分辨质谱技术结合UNIFI高通量筛查面膜类化妆品中141种非法添加成分
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作者 范晨丽 王海波 +1 位作者 蒋培 申二永 《分析科学学报》 北大核心 2025年第4期405-414,共10页
建立了一种基于超高效液相色谱-四极杆-飞行时间高分辨质谱技术,结合UNIFI软件的高通量筛查方法,用于检测面膜类化妆品中141种非法添加成分。样品经饱和氯化钠溶液溶解后,加入含0.5%甲酸的乙腈进行超声提取,采用Oasis HLB固相萃取小柱... 建立了一种基于超高效液相色谱-四极杆-飞行时间高分辨质谱技术,结合UNIFI软件的高通量筛查方法,用于检测面膜类化妆品中141种非法添加成分。样品经饱和氯化钠溶液溶解后,加入含0.5%甲酸的乙腈进行超声提取,采用Oasis HLB固相萃取小柱净化。使用BEH C18(100 mm×2.1 mm,1.7μm)色谱柱分离,并在电喷雾离子源(ESI)正负扫描模式下,采用MS^(E)模式采集化合物的质谱信息。通过化合物的母离子和二级碎片离子的精准质量数以及保留时间等参数,利用UNIFI软件构建筛查数据库。最终通过基质标曲外标法进行定量分析。141种非法添加成分响应值与浓度呈良好线性关系(R^(2)>0.99),检出限为0.15~1.35 mg/kg;定量限为0.45~4.05 mg/kg。空白基质样品(面贴式乳液剂和涂抹式膏霜剂)中加入3个水平点的平均回收率为63.0%~124.5%;日内、日间相对标准偏差(RSD)分别为1.2%~9.1%(n=6)和1.3%~13.9%(n=3)。采用该方法测定市售86批面膜类产品,检出1批氯倍他索丙酸脂和3批酮康唑,检出含量范围为0.3~561.3 mg/kg。该方法操作简便、高效准确,具有良好的专属性,可实现面膜类化妆品中141种非法添加成分的高通量筛查,为化妆品质量监管提供了可靠的技术支持。 展开更多
关键词 UPLC-Q-TOF-MS^(E) 面膜类化妆品 非法添加成分 unifi 高通量筛查
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Towards Efficient Vehicle Recognition:A Unified System for VMMR,ANPR,and Color Classification
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作者 Saad Sadiq Kashif Sultan +2 位作者 Muhammad Sheraz Teong Chee Chuah Muhammad Usman Hashmi 《Computers, Materials & Continua》 2025年第11期3945-3963,共19页
Vehicle recognition plays a vital role in intelligent transportation systems,law enforcement,access control,and security operations—domains that are becoming increasingly dynamic and complex.Despite advancements,most... Vehicle recognition plays a vital role in intelligent transportation systems,law enforcement,access control,and security operations—domains that are becoming increasingly dynamic and complex.Despite advancements,most existing solutions remain siloed,addressing individual tasks such as vehicle make and model recognition(VMMR),automatic number plate recognition(ANPR),and color classification separately.This fragmented approach limits real-world efficiency,leading to slower processing,reduced accuracy,and increased operational costs,particularly in traffic monitoring and surveillance scenarios.To address these limitations,we present a unified framework that consolidates all three recognition tasks into a single,lightweight system.The framework utilizes MobileNetV2 for efficient VMMR,YOLO(You Only Look Once)for accurate license plate detection,and histogram-based clustering in the HSV color space for precise color identification.Rather than optimizing each module in isolation,our approach emphasizes tight integration,enabling improved performance and reliability.The system also features adaptive image calibration and robust algorithmic enhancements to ensure consistent results under varying environmental conditions.Experimental evaluations demonstrate that the proposedmodel achieves a combined accuracy of 93.3%,outperforming traditional methods and offering practical scalability for deployment in real-world transportation infrastructures. 展开更多
关键词 VMMR ANPR unified framework deep learning
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Unified construction of prenylated and reverse-prenylated oxindoles from isoprene launched by Ni catalysis
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作者 Ying-Ying Liu Ying Li +4 位作者 Xue-Ting Li Su-Yang Xu Ding-Wei Ji Xiang-Ping Hu Qing-An Chen 《Chinese Journal of Catalysis》 2025年第3期444-454,共11页
As important natural and pharmaceutical motifs,the catalytic construction of structurally diverse 3,3-disubstituted oxindoles often requires elaborate synthetic efforts on optimizations.Herein,we developed a simple an... As important natural and pharmaceutical motifs,the catalytic construction of structurally diverse 3,3-disubstituted oxindoles often requires elaborate synthetic efforts on optimizations.Herein,we developed a simple and divergent approach for constructing reverse-prenylated and prenylated oxindoles launched by Ni catalysis with bulk chemical isoprene.Using C3-unsubstituted oxindoles as starting materials,mono reverse-prenylation was demonstrated in high chemo-and regioselectivities facilitated by the combination of Ni(0)and monodentate phosphine ligand.Using the obtained reverse-prenylated oxindoles as versatile synthon,substitutions at the pseudobenzylic position with various electrophiles created vicinal quaternary centers in a concise way.With the help of additives(PPh3 and NaH),air could be directly used as green oxidant to construct prenylated and reverse-prenylatedα-hydroxy-oxindoles divergently from the same substrates.In situ esterification of prenylatedα-hydroxy-oxindoles allowed subsequent Friedel-Crafts substitutions with diverse nucleophiles to deliver prenyl substituted dimeric or spiro-oxindoles.This protocol provides a divergent synthetic approach for the construction of highly functionalized 3,3-disubstituted oxindoles,which have been otherwise difficult to access in a unified approach. 展开更多
关键词 Nickel catalysis unified construction ISOPRENE (Reverse-)prenylation OXINDOLE
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Ground reaction curves for strain-softening rock masses with ground reinforcement based on unified strength criterion
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作者 CHEN Xuan-hao ZHANG Ding-li +1 位作者 SUN Zhen-yu CHEN Wen-bo 《Journal of Central South University》 2025年第9期3383-3404,共22页
Ground reinforcement is crucial for tunnel construction, especially in soft rock tunnels. Existing analytical models are inadequate for predicting the ground reaction curves (GRCs) for reinforced tunnels in strain-sof... Ground reinforcement is crucial for tunnel construction, especially in soft rock tunnels. Existing analytical models are inadequate for predicting the ground reaction curves (GRCs) for reinforced tunnels in strain-softening (SS) rock masses. This study proposes a novel analytical model to determine the GRCs of SS rock masses, incorporating ground reinforcement and intermediate principal stress (IPS). The SS constitutive model captures the progressive post- peak failure, while the elastic-brittle model simulates reinforced rock masses. Nine combined states are innovatively investigated to analyze plastic zone development in natural and reinforced regions. Each region is analyzed separately, and coupled through boundary conditions at interface. Comparison with three types of existing models indicates that these models overestimate reinforcement effects. The deformation prediction errors of single geological material models may exceed 75%. Furthermore, neglecting softening and residual zones in natural regions could lead to errors over 50%. Considering the IPS can effectively utilize the rock strength to reduce tunnel deformation by at least 30%, thereby saving on reinforcement and support costs. The computational results show a satisfactory agreement with the monitoring data from a model test and two tunnel projects. The proposed model may offer valuable insights into the design and construction of reinforced tunnel engineering. 展开更多
关键词 ground reinforcement STRAIN-SOFTENING unified strength criterion tunnel responses analytical model
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Stress gradient analytic solution and reasonable support prestress of roadway surrounding rock based on unified strength criterion:A case study
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作者 JING Suo-lin WEN Zhi-jie +2 位作者 ZUO Yu-jun LI Qiu-ju HAO Peng 《Journal of Central South University》 2025年第2期449-468,共20页
The stress gradient of surrounding rock and reasonable prestress of support are the keys to ensuring the stability of roadways.The elastic-plastic analytical solution for surrounding rock was derived based on unified ... The stress gradient of surrounding rock and reasonable prestress of support are the keys to ensuring the stability of roadways.The elastic-plastic analytical solution for surrounding rock was derived based on unified strength theory.A model for solving the stress gradient of the surrounding rock with the intermediate principal stress parameter b was established.The correctness and applicability of the solution for the stress gradient in the roadway surrounding rock was verified via multiple methods.Furthermore,the laws of stress,displacement,and the plastic zone of the surrounding rock with different b values and prestresses were revealed.As b increases,the stress gradient in the plastic zone increases,and the displacement and plastic zone radius decrease.As the prestress increases,the peak stress shifts toward the sidewalls,and the stress and stress gradient increments decrease.In addition,the displacement increment and plastic zone increment were proposed to characterize the support effect.The balance point of the plastic zone area appears before that of the displacement zone.The relationship between the stress gradient compensation coefficient and the prestress is obtained.This study provides a research method and idea for determining the reasonable prestress of support in roadways. 展开更多
关键词 PRESTRESS support compensation surrounding rock damage stress gradient analytic solution unified strength theory
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Two imaginarity monotones induced by unified(α,β)-relative entropy
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作者 Chuanfa Wu Zhaoqi Wu 《Communications in Theoretical Physics》 2025年第9期24-34,共11页
Complex numbers play a pivotal role in both mathematics and physics,particularly in quantum mechanics,and are extensively utilized to depict the behavior of microscopic particles.Recognizing the significance of comple... Complex numbers play a pivotal role in both mathematics and physics,particularly in quantum mechanics,and are extensively utilized to depict the behavior of microscopic particles.Recognizing the significance of complex numbers,a framework of imaginarity resource theory has recently been established.In this work,we propose two types of imaginarity monotones induced by the unified(α,β)-relative entropy and investigate their properties.Moreover,we give explicit examples to illustrate our results. 展开更多
关键词 quantum resource theory imaginarity monotone unified(α β)-relative entropy
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Associated network family of the unified piecewise linear chaotic family and their relevance
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作者 Haoying Niu Jie Liu 《Chinese Physics B》 2025年第4期323-333,共11页
Duality analysis of time series and complex networks has been a frontier topic during the last several decades.According to some recent approaches in this direction,the intrinsic dynamics of typical nonlinear systems ... Duality analysis of time series and complex networks has been a frontier topic during the last several decades.According to some recent approaches in this direction,the intrinsic dynamics of typical nonlinear systems can be better characterized by considering the related nonlinear time series from the perspective of networks science.In this paper,the associated network family of the unified piecewise-linear(PWL)chaotic family,which can bridge the gap of the PWL chaotic Lorenz system and the PWL chaotic Chen system,was firstly constructed and analyzed.We constructed the associated network family via the original and the modified frequency-degree mapping strategy,as well as the classical visibility graph and horizontal visibility graph strategy,after removing the transient states.Typical related network characteristics,including the network fractal dimension,of the associated network family,are computed with changes of single key parameter a.These characteristic vectors of the network are also compared with the largest Lyapunov exponent(LLE)vector of the related original dynamical system.It can be found that,some network characteristics are highly correlated with LLE vector of the original nonlinear system,i.e.,there is an internal consistency between the largest Lyapunov exponents,some typical associated network characteristics,and the related network fractal dimension index.Numerical results show that the modified frequency-degree mapping strategy can demonstrate highest correlation,which means it can behave better to capture the intrinsic characteristics of the unified PWL chaotic family. 展开更多
关键词 nonlinear time series unified PWL chaotic family Lyapunov exponents complex network
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Design of a Private Cloud Platform for Distributed Logging Big Data Based on a Unified Learning Model of Physics and Data
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作者 Cheng Xi Fu Haicheng Tursyngazy Mahabbat 《Applied Geophysics》 2025年第2期499-510,560,共13页
Well logging technology has accumulated a large amount of historical data through four generations of technological development,which forms the basis of well logging big data and digital assets.However,the value of th... Well logging technology has accumulated a large amount of historical data through four generations of technological development,which forms the basis of well logging big data and digital assets.However,the value of these data has not been well stored,managed and mined.With the development of cloud computing technology,it provides a rare development opportunity for logging big data private cloud.The traditional petrophysical evaluation and interpretation model has encountered great challenges in the face of new evaluation objects.The solution research of logging big data distributed storage,processing and learning functions integrated in logging big data private cloud has not been carried out yet.To establish a distributed logging big-data private cloud platform centered on a unifi ed learning model,which achieves the distributed storage and processing of logging big data and facilitates the learning of novel knowledge patterns via the unifi ed logging learning model integrating physical simulation and data models in a large-scale functional space,thus resolving the geo-engineering evaluation problem of geothermal fi elds.Based on the research idea of“logging big data cloud platform-unifi ed logging learning model-large function space-knowledge learning&discovery-application”,the theoretical foundation of unified learning model,cloud platform architecture,data storage and learning algorithm,arithmetic power allocation and platform monitoring,platform stability,data security,etc.have been carried on analysis.The designed logging big data cloud platform realizes parallel distributed storage and processing of data and learning algorithms.The feasibility of constructing a well logging big data cloud platform based on a unifi ed learning model of physics and data is analyzed in terms of the structure,ecology,management and security of the cloud platform.The case study shows that the logging big data cloud platform has obvious technical advantages over traditional logging evaluation methods in terms of knowledge discovery method,data software and results sharing,accuracy,speed and complexity. 展开更多
关键词 unified logging learning model logging big data private cloud machine learning
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BestMan:a modular mobile manipulator platform for embodied AI with unified simulation-hardware APIs
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作者 Kui YANG Nieqing CAO +3 位作者 Beichen SHAO Xingchen WANG Yan DING Chao CHEN 《Frontiers of Computer Science》 2025年第9期149-151,共3页
1Introduction Embodied Artificial Intelligence(Embodied AI)has recently become a key research focus[1].It emphasizes agents'abilities to perceive,comprehend,and act in physical worlds to complete tasks.Simulation ... 1Introduction Embodied Artificial Intelligence(Embodied AI)has recently become a key research focus[1].It emphasizes agents'abilities to perceive,comprehend,and act in physical worlds to complete tasks.Simulation platforms are essential in this area,as they simulate agent behaviors in set environments and tasks,thereby accelerating algorithm validation and optimization.However,constructing such a platform presents several challenges. 展开更多
关键词 unified simulation hardware APIs simulate agent behaviors embodied artificial intelligence embodied artificial intelligence embodied ai modular mobile manipulator platform simulation platforms
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基于UPLC-QTOF-MS和UNIFI软件的中药非法添加色素筛查平台建设
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作者 李明华 张佳婷 +5 位作者 王献瑞 张萍 张毅 周娟 程显隆 魏锋 《中国现代中药》 CAS 2024年第12期2063-2069,共7页
目的:基于超高效液相色谱-四级杆飞行时间质谱法(UPLC-QTOF-MS)分析和UNIFI软件,建立包含45种常见中药非法添加色素的筛查平台,以期为中药材(饮片)质量监管提供技术方法,提高监管效率。方法:采用Waters ACQUITY UPLC BEH-C18色谱柱,以5 ... 目的:基于超高效液相色谱-四级杆飞行时间质谱法(UPLC-QTOF-MS)分析和UNIFI软件,建立包含45种常见中药非法添加色素的筛查平台,以期为中药材(饮片)质量监管提供技术方法,提高监管效率。方法:采用Waters ACQUITY UPLC BEH-C18色谱柱,以5 mmol·L^(–1)的乙酸铵水溶液和乙腈为流动相梯度洗脱,流速为0.4 mL·min^(–1),同时利用UPLC-QTOF-MS/MSE进行质谱检测分析,基于电喷雾离子源(ESI)在m/z 50~1200范围内进行正、负离子扫描,并与色素对照试剂进行比对。最后,将45种色素的名称、CAS号、分子式、结构图(.mol格式)、碎片离子等信息导入UNIFI软件,构建中药非法添加色素筛查平台并进行验证分析。结果:成功构建了包含45种添加色素的快速筛查平台,45种色素检测下限为0.33~24.83 ng·mL^(–1),此外对蒲黄、红花、五味子3个品种的市售中药进行了色素筛查,检出有红色和黄色添加色素如金橙Ⅱ、柠檬黄和皂黄等。结论:建立的色素快速筛查平台可快速、简便、高效地实现中药非法添加色素的筛查并有效提高药品监管效率。 展开更多
关键词 色素 超高效液相色谱-四级杆飞行时间质谱法 非法添加 unifi软件
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Towards a Unified Theory of Everything: Integrating Discrete Time Evolution and Classical-Quantum Dynamics in the Advanced Observer Model (AOM)
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作者 Joseph H. C. Wong 《Journal of Quantum Information Science》 2024年第4期196-233,共38页
This paper introduces the Advanced Observer Model (AOM), a novel framework that integrates classical mechanics, quantum mechanics, and relativity through the observer’s role in constructing reality. Central to the AO... This paper introduces the Advanced Observer Model (AOM), a novel framework that integrates classical mechanics, quantum mechanics, and relativity through the observer’s role in constructing reality. Central to the AOM is the Static Configuration/Dynamic Configuration (SC/DC) conjugate, which examines physical systems through the interaction between static spatial configurations and dynamic quantum states. The model introduces a Constant Frame Rate (CFR) to quantize time perception, providing a discrete model for time evolution in quantum systems. By modifying the Schrödinger equation with CFR, the AOM bridges quantum and classical physics, offering a unified interpretation where classical determinism and quantum uncertainty coexist. A key feature of the AOM is its energy scaling model, where energy grows exponentially with spatial dimensionality, following the relationshipE∝(π)n. This dimensional scaling connects the discrete time perception of the observer with both quantum and classical energy distributions, providing insights into the nature of higher-dimensional spaces. Additionally, the AOM posits that spacetime curvature arises from quantum interactions, shaped by the observer’s discrete time perception. The model emphasizes the observer’s consciousness as a co-creator of reality, offering new approaches to understanding the quantum-classical transition. While speculative, the AOM opens new avenues for addressing foundational questions in quantum mechanics, relativity, dimensionality, and the nature of reality. 展开更多
关键词 Quantum Mechanics Schrödinger Equation Constant Frame Rate (CFR) Advanced Observer Model (AOM) Relativistic Physics Classical-Quantum Transition Wave Function Discrete Time Evolution Spacetime Geometry unified Theory Quantum-Classical unification Observer-Dependent Reality Energy Scaling
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Unified deep learning model for predicting fundus fluorescein angiography image from fundus structure image 被引量:8
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作者 Yiwei Chen Yi He +3 位作者 Hong Ye Lina Xing Xin Zhang Guohua Shi 《Journal of Innovative Optical Health Sciences》 SCIE EI CSCD 2024年第3期105-113,共9页
The prediction of fundus fluorescein angiography(FFA)images from fundus structural images is a cutting-edge research topic in ophthalmological image processing.Prediction comprises estimating FFA from fundus camera im... The prediction of fundus fluorescein angiography(FFA)images from fundus structural images is a cutting-edge research topic in ophthalmological image processing.Prediction comprises estimating FFA from fundus camera imaging,single-phase FFA from scanning laser ophthalmoscopy(SLO),and three-phase FFA also from SLO.Although many deep learning models are available,a single model can only perform one or two of these prediction tasks.To accomplish three prediction tasks using a unified method,we propose a unified deep learning model for predicting FFA images from fundus structure images using a supervised generative adversarial network.The three prediction tasks are processed as follows:data preparation,network training under FFA supervision,and FFA image prediction from fundus structure images on a test set.By comparing the FFA images predicted by our model,pix2pix,and CycleGAN,we demonstrate the remarkable progress achieved by our proposal.The high performance of our model is validated in terms of the peak signal-to-noise ratio,structural similarity index,and mean squared error. 展开更多
关键词 Fundus fluorescein angiography image fundus structure image image translation unified deep learning model generative adversarial networks
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Unified Field Equation Generated by Longitudinal Electromagnetic (LEM) Waves 被引量:2
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作者 Jiang Jian-zhong Zhang Xiang-qian 《Journal of Environmental Science and Engineering(B)》 CAS 2024年第5期181-191,共11页
According to special relativity,the relationship of electromagnetic conversion in a linear moving vacuum and the relationship formula between the magnetic vector potential/scalar potential and the LEM(Longitudinal Ele... According to special relativity,the relationship of electromagnetic conversion in a linear moving vacuum and the relationship formula between the magnetic vector potential/scalar potential and the LEM(Longitudinal Electromagnetic)waves,it is inferred that the spherical vacuum space we are in undergoes outward helical motion at the speed of light following the right-hand screw rule,accompanied by a radial space expansion motion far less than the speed of light.Based on this space basis,we derive a unified field equation indicating that the gravitational field might be equivalent to the acceleration field of the radial expansion motion of our vacuum space,the strong nuclear force field presumably is generated by the light-rotation angular velocity of our space,the weak nuclear force field is most probably produced by its radial expansion motion and the electromagnetic field is undoubtedly produced by the radial linear motion of our space at the speed of light.We have also demonstrated both theoretically and experimentally that the LEM waves can generate artificial gravitational fields,and the LEM waves are the material basis of the unified field theory.Essentially,on Earth,time is the result of the relativistic length contraction effect caused by the radial space expansion speed,which leads to the rate of change of distance in the radial dimension on the unit radial space expansion speed.Moreover,based on the length contraction effect in special relativity,the time and space generated by the outward helical motion of space at the speed of light can be expressed as zero.This indicates that such motion not only does not affect the seemingly perpetually stationary space that we can constantly perceive but also enables the gravitational field formula to remain unchanged in our space.They constitute the spatio-temporal basis of the unified field theory.Based on our unified field theory,we have also discussed some forward-looking perspectives,such as motion at the speed of light,anti-gravitation fields,and interstellar travel. 展开更多
关键词 QED(quantum electrodynamics) LEM wave electromagnetic induction unified field equation artificial gravitation field.
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Autonomous relative optical navigation based on unified modeling of external systematic errors
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作者 Dayi WANG Bowen SUN +2 位作者 Maodeng LI Jiaxing LI Haiyin ZHOU 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2024年第3期282-289,共8页
To solve the problem that external systematic errors of the optical camera cannot be fully estimated due to limited computing resources,a unified dimensionality reduction representation method for the external systema... To solve the problem that external systematic errors of the optical camera cannot be fully estimated due to limited computing resources,a unified dimensionality reduction representation method for the external systematic errors of the optical camera is proposed,and autonomous relative optical navigation is realized.The camera translational and misalignment errors are converted into a three-dimensional rotation error,whose differential model can be established through specific attitude control and appropriate assumption.Then,the rotation error and the relative motion state are jointly estimated in an augmented Kalman filter framework.Compared with the traditional method that estimates the camera translational and misalignment errors,the proposed method reduces the computational complexity in that the estimated state dimension is reduced.Furthermore,as demonstrated by numerical simulation,the estimation accuracy is improved significantly. 展开更多
关键词 unified model Systematic errors Optical navigation Observability analysis CALIBRATION
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Unified numerical predictor-corrector guidance based on characteristic model
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作者 MENG Bin ZHANG Hangning ZHAO Yunbo 《中国空间科学技术(中英文)》 CSCD 北大核心 2024年第4期40-49,共10页
Aerocapture is one of the key technologies for low-cost transportation,with high demands of autonomy,accuracy,and robustness of guidance and control,due to its high reliability requirements for only one chance of tryi... Aerocapture is one of the key technologies for low-cost transportation,with high demands of autonomy,accuracy,and robustness of guidance and control,due to its high reliability requirements for only one chance of trying.A unified numerical predictor-corrector guidance method based on characteristic models for aerocapture is proposed.The numerical predictor-corrector guidance method is used to achieve autonomy and high accuracy,and the characteristic model control method is introduced to achieve robustness.At the same time,by transforming path constraints,characteristic model equations including apogee deviation and altitude differentiation are established.Based on the characteristic model equations,a unified guidance law which can satisfy path constraints and guidance objectives simultaneously is designed.In guidance problems,guidance deviation is not directly obtained from the output of the dynamics at present,but is calculated through integral and algebraic equations.Therefore,the method of directly discretizing differential equations cannot be used to establish characteristic models,which brings great difficulty to characteristic modeling.A method for characteristic modeling of guidance problems is proposed,and convergence analysis of the proposed guidance law is also provided.Finally,a joint numerical simulation of guidance and control considering navigation deviation and various uncertainties is conducted to verify the effectiveness of the proposed method.The proposed unified method can be extended to general aerodynamic entry guidance designs,providing theoretical and methodological support for them. 展开更多
关键词 aerocapture path constraint characteristic model unified numerical predictor-corrector guidance CONVERGENCE
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Isotopic dependence of the yield ratios of light fragments from different projectiles and their unified neutron skin thicknesses
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作者 Ting-Zhi Yan Shan Li 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期228-236,共9页
The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(ever... The yield ratios of neutron-proton(R(n/p))and^(3)H-^(3)He(R(^(3)H∕^(3)He))with reduced rapidity from 0 to 0.5 were simulated at 50 MeV/u even-even ^(36−56)Ca+^(40)Ca,even-even ^(48−78)Ni+^(58)Ni,and ^(100−139)Sn(every third isotopes)+112 Sn for full reduced impact parameters using the isospin-dependent quantum molecular dynamics(IQMD)model.The neutron and proton density distributions and root-mean-square radii of the reaction systems were obtained using the Skyrme-Hartree-Fock model,which was used for the phase space initialization of the projectile and target in IQMD.We defined the unified neutron skin thickness asΔRnp=<r^(2)>^(1∕2) n−<r^(2)>^(1∕2)p,which was negative for neutron-deficient nuclei.The unifiedΔRnp values for nuclei with the same relative neutron excess from different isotopic chains were nearly equal,except for extreme neutron-rich isotopes,which is a type of scaling behavior.The yield ratios of the three isotopic chain-induced reactions,which depended on the reduced impact parameter and unified neutron skin thickness,were studied.The results showed that both R(n/p)and R(^(3)H∕^(3)He)decreased with a reduced impact parameter for extreme neutron-deficient isotopes;however,they increased with reduced impact parameters for extreme neutron-rich isotopes,and increased with theΔRnp of the projectiles for all reduced impact parameters.In addition,a scaling phenomenon was observed betweenΔR np and the yield ratios in peripheral colli-sions from different isotopic chain projectiles(except for extreme neutron-rich isotopes).Thus,R(n/p)and R(^(3)H∕^(3)He)from peripheral collisions were suggested as experimental probes for extracting the neutron or proton skin thicknesses of non-extreme neutron-rich nuclei from different isotopic chains. 展开更多
关键词 Exotic nuclei unified neutron skin thickness Yield ratios IQMD
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Assessing the range of blasting-induced cracks in the surrounding rock of deeply buried tunnels based on the unified strength theory
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作者 LI Liang CHEN Jia-jun +3 位作者 ZHAO Lian-heng HE Ke-pei HU Shi-hong LI Hua-long 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2341-2364,共24页
Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety risks.However,previous theoretical studies on the range of blasting-in... Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety risks.However,previous theoretical studies on the range of blasting-induced cracks often ignore the impact of the in-situ stress,especially that of the intermediate principal stress.The particle displacement−crack radius relationship was established in this paper by utilizing the blasthole cavity expansion equation,and theoretical analytical formulas of the stress−displacement relationship and the crack radius were derived with unified strength theory to accurately assess the range of cracks in deep surrounding rock under a blasting load.Parameter analysis showed that the crushing zone size was positively correlated with in-situ stress,intermediate principal stress,and detonation pressure,whereas negatively correlated with Poisson ratio and decoupling coefficient.The dilatancy angle-crushing zone size relationship exhibited nonmonotonic behavior.The relationships in the crushing zone and the fracture zone exhibited opposite trends under the influence of only in-situ stress or intermediate principal stress.As the in-situ stress increased from 0 to 70 MPa,the rate of change in the crack range and the attenuation rate of the peak vibration velocity gradually slowed. 展开更多
关键词 deep drilling and blasting cracks in surrounding rock unified strength theory intermediate principle stress in-situ stress cavity expansion dilatancy characteristics
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Unified Control Theory from PID to ACPID
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作者 Zhezhao Zeng Yuqi Tang 《Advances in Pure Mathematics》 2024年第7期523-545,共23页
To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been propose... To address the challenge of achieving unified control across diverse nonlinear systems, a comprehensive control theory spanning from PID (Proportional-Integral-Derivative) to ACPID (Auto-Coupling PID) has been proposed. The primary concept is to unify all intricate factors, including internal dynamics and external bounded disturbance, into a single total disturbance. This enables the mapping of various nonlinear systems onto a linear disturbance system. Based on the theory of PID control and the characteristic equation of a critically damping system, Zeng’s stabilization rules (ZSR) and an ACPID control force based on a single speed factor have been designed. ACPID control theory is both simple and practical, with significant scientific significance and application value in the field of control engineering. 展开更多
关键词 Insert Nonlinear Systems PID Control ACPID Control Total Disturbance unified Control Theory Zeng’s Stabilization Rules (ZSR)
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