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A Perspective on Shortwave Radiative Energy Flows in the Earth System
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作者 Jake J.GRISTEY 《Advances in Atmospheric Sciences》 2026年第2期295-306,共12页
The study of shortwave(SW) radiation and its interactions with our planet has proven critical for advancing the understanding of the Earth–atmosphere system. Here, the author shares an accessible and high-level persp... The study of shortwave(SW) radiation and its interactions with our planet has proven critical for advancing the understanding of the Earth–atmosphere system. Here, the author shares an accessible and high-level perspective on recent progress, surprises encountered, and promising future research directionsa. A brief context for the study of SW radiation is provided, after which three specific aspects are focused upon that the author considers particularly important. First, the significance of three-dimensional(3D) SW radiative effects is highlighted via impacts on surface downward SW radiation in complex cloud fields. Crucially, it is shown that probability distributions of surface radiation can only be reliably simulated when accounting for 3D effects, which has implications for various applications and next-generation atmospheric modeling. Second, the significance of the often overlooked diurnal cycle in global top-of-atmosphere upward SW radiation is underscored by quantifying the controlling properties and processes. Opportunities for improved future satellite observations of the global diurnal cycle are noted. Third, the wealth of information provided by the spectral dimension of SW radiation is demonstrated through the extraction and attribution of SW spectral signatures. It is argued that further exploration of the spectral dimension, aided by the recently launched and upcoming suite of spectrally resolved SW satellite observations, promises a new era of SW radiation research. 展开更多
关键词 shortwave radiation Earth radiation budget three-dimensional radiative effects diurnal cycle spectral variability
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First systematic identification of triple-mode Auroral Kilometric Radiation using Arase polarization data
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作者 YiHua He SanGuang Li +8 位作者 HongMing Yang Sai Zhang YuYue Jin Si Liu ZhongLei Gao FuLiang Xiao ZhaoGuo He JiaWen Tang Ping Li 《Earth and Planetary Physics》 2026年第1期117-125,共9页
Auroral kilometric radiation(AKR),a fundamental plasma emission in Earth's magnetosphere,exhibits three characteristic modes:the right-handed extraordinary(R-X),left-handed ordinary(L-O)and left-handed extraordina... Auroral kilometric radiation(AKR),a fundamental plasma emission in Earth's magnetosphere,exhibits three characteristic modes:the right-handed extraordinary(R-X),left-handed ordinary(L-O)and left-handed extraordinary(L-X)modes.The role of AKR in magnetosphere−ionosphere−atmosphere coupling depends sensitively on its wave mode.While previous studies have primarily focused on the dominant R-X mode,we present the first systematic identification of all three modes using a practical polarization analysis method based on Arase satellite observations.This method employs a spin-axis-relative Ratio:when the satellite's spin axis aligns with the background magnetic field,a positive(negative)Ratio indicates the right-handed(left-handed)polarization,with reversal under anti-parallel conditions.Combined polarization-frequency analysis reveals that R-X,L-O,and L-X modes can exist in both dayside and nightside regions,with power spectral densities up to 10^(-6)mV^(2)m^(-2)Hz^(-1).This study resolves long-standing ambiguities in AKR mode classification and has implications for understanding AKR-induced electron dynamics. 展开更多
关键词 Auroral kilometric radiation wave mode POLARIZATION
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Detection of white matter microstructural changes in patients with systemic lupus erythematosus based on multiple diffusion models and related diffusion metrics
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作者 Zhenxing Li Huanhuan Li +5 位作者 Bailing Tian Huiyang Liu Yueluan Jiang Pingting Yang Guoguang Fan Hu Liu 《Neural Regeneration Research》 2026年第6期2467-2474,共8页
Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle... Some patients with systemic lupus erythematosus experience neuropsychiatric symptoms.Although magnetic resonance imaging can detect abnormal signals in the white matter of the brain,conventional methods often struggle to accurately capture microstructural changes.Various diffusion models have been used to study white matter in systemic lupus erythematosus;however,comparative analyses of their sensitivity and specificity for detecting microstructural changes remain insufficient.To address this,our team designed a diagnostic trial that used multimodal diffusion imaging techniques to observe white matter microstructural changes in patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with an aim to identify key diagnostic biomarkers for these patients.Patients with active lupus who received treatment at the Department of Rheumatology and Immunology,The First Affiliated Hospital of China Medical University,from September 2023 to March 2024 were recruited.According to the standards of the American College of Rheumatology,patients with systemic lupus erythematosus who had neuropsychiatric symptoms were assigned to the systemic lupus erythematosus group,whereas those without neuropsychiatric symptoms were assigned to the non-systemic lupus erythematosus group.Additionally,healthy volunteers matched by region,sex,and age were recruited as controls.All three groups underwent the same diffusion magnetic resonance imaging examination protocol to compare differences in diffusion parameters.Advanced diffusion imaging models were able to sensitively detect microstructural changes in the white matter fibers of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,with specific diffusion parameters showing significant abnormalities in key brain regions.In the left superior longitudinal fasciculus subregion and the right thalamic radiations of patients with systemic lupus erythematosus who had neuropsychiatric symptoms,we also identified abnormal diffusion characteristics that were clearly correlated with disease activity,suggesting that microstructural changes in these areas may reflect the dynamic process of neuroinflammatory damage.The present study addresses critical challenges in the diagnosis of systemic lupus erythematosus by identifying specific white matter imaging biomarkers and elucidating the association between microstructural damage and clinical manifestations.The main contributions of our study include:1)establishing axial regression probability parameters from mean apparent propagator magnetic resonance imaging as sensitive biomarkers for systemic lupus erythematosus,particularly in the third subregion of the left superior longitudinal fasciculus;2)demonstrating that multimodal diffusion imaging may be superior to conventional diffusion tensor imaging for detecting white matter microstructural abnormalities in patients with systemic lupus erythematosus;and 3)integrating tract-based spatial statistics with clinically relevant analyses to link imaging findings to pathological mechanisms. 展开更多
关键词 diffusion kurtosis imaging diffusion tensor imaging mean apparent propagator neurite orientation dispersion and density imaging neuropsychiatric systemic lupus erythematosus return to axis probability return to origin probability superior longitudinal fasciculus-3 superior thalamic radiation tract-based spatial statistics white matter microstructure
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Experimental Research of the Radiator Thermal Performance Test Equipment and Its Application in Heating System 被引量:1
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作者 Lian Zhang Linjun Fan +3 位作者 Xin Xu Baowen Cao Heng Zhang Lihong Song 《Energy Engineering》 EI 2021年第2期399-410,共12页
Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflo... Radiator thermal performance test equipment plays a key role in the processing of developing a new type of heat radiator and its application products.The precise of temperature controlling,temperature measuring andflow measuring are the vital factors for a radiator thermal performance test equipment.Based on the above back-ground,this paper improves the measurement and control system of radiator thermal performance test equip-ment,which improves the accuracy of the radiator thermal performance test equipment.This paper also optimizes the software and hardware system simultaneously so as to improve the precision of the auto-test system of test equipment.Theflow rate ranges from 175 kg/h to 178 kg/h under different conditions.The average is 176.5 kg/h and the deviation rates are from 1.62%to 1.97%.The heat produced under various conditions is different.The maximum is 4.3 kW and the minimum is 4.2 kW for condition 1,the maximum is 3.3 kW and the minimum is 3.2 kW for condition 2 and the maximum is 1.95 kW and the minimum is 1.89 kW for condition 3.However,the deviation rate is about 2.9%,which shows that the device has high stability and high precision.This paper studies a new electronic heat cost allocate meter test method by radiator thermal performance test equipment at the same time.This paper tests temperature changes through four measures points and gets a result appeared as a heat backup which should be avoided when using in the test of electronic heat cost allocate meter.Some experiences and references could be gained for further research in the heating system from this test and research. 展开更多
关键词 Electronic heat cost allocate meter radiator precise control HEATING
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The protective effects of melatonin against electromagnetic waves of cell phones in animal models:A systematic review 被引量:1
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作者 Mohammad Amiri Habibolah Khazaie Masoud Mohammadi 《Animal Models and Experimental Medicine》 2025年第4期629-637,共9页
Background:Due to the widespread use of cell phone devices today,numerous re-search studies have focused on the adverse effects of electromagnetic radiation on human neuropsychological and reproductive systems.In most... Background:Due to the widespread use of cell phone devices today,numerous re-search studies have focused on the adverse effects of electromagnetic radiation on human neuropsychological and reproductive systems.In most studies,oxidative stress has been identified as the primary pathophysiological mechanism underlying the harmful effects of electromagnetic waves.This paper aims to provide a holistic review of the protective effects of melatonin against cell phone-induced electromag-netic waves on various organs.Methods:This study is a systematic review of articles chosen by searching Google Scholar,PubMed,Embase,Scopus,Web of Science,and Science Direct using the key-words‘melatonin’,‘cell phone radiation’,and‘animal model’.The search focused on articles written in English,which were reviewed and evaluated.The PRISMA process was used to review the articles chosen for the study,and the JBI checklist was used to check the quality of the reviewed articles.Results:In the final review of 11 valid quality-checked articles,the effects of me-latonin in the intervention group,the effects of electromagnetic waves in the case group,and the amount of melatonin in the chosen organ,i.e.brain,skin,eyes,testis and the kidney were thoroughly examined.The review showed that electromagnetic waves increase cellular anti-oxidative activity in different tissues such as the brain,the skin,the eyes,the testis,and the kidneys.Melatonin can considerably augment the anti-oxidative system of cells and protect tissues;these measurements were sig-nificantly increased in control groups.Electromagnetic waves can induce tissue atro-phy and cell death in various organs including the brain and the skin and this effect was highly decreased by melatonin.Conclusion:Our review confirms that melatonin effectively protects the organs of an-imal models against electromagnetic waves.In light of this conclusion and the current world-wide use of melatonin,future studies should advance to the stages of human clinical trials.We also recommend that more research in the field of melatonin physi-ology is conducted in order to protect exposed cells from dying and that melatonin should be considered as a pharmaceutical option for treating the complications result-ing from electromagnetic waves in humans. 展开更多
关键词 animal model cell phone radiation MELATONIN
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Applications of photon-counting CT in oncologic imaging:A systematic review 被引量:1
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作者 Arosh S Perera Molligoda Arachchige Anna Dashiell +7 位作者 Anton Shiraan Jesuraj Antonia Immacolata D’Urso Benedetta Fiore Martina Cattaneo Emilia Pierzynska Sandra Szydelko Francesca Romana Centini Yash Verma 《World Journal of Radiology》 2025年第8期74-83,共10页
BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with ... BACKGROUND Photon-counting detector(PCD)CT represents a transformative advancement in radiological imaging,offering superior spatial resolution,enhanced contrast-tonoise ratio,and reduced radiation dose compared with the conventional energyintegrating detector CT.AIM To evaluate PCD CT in oncologic imaging,focusing on its role in tumor detection,staging,and treatment response assessment.METHODS We performed a systematic PubMed search from January 1,2017 to December 31,2024,using the keywords“photon-counting CT”,“cancer”,and“tumor”to identify studies on its use in oncologic imaging.We included experimental studies on humans or human phantoms and excluded reviews,commentaries,editorials,non-English,animal,and non-experimental studies.Study selection followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Out of 175 initial studies,39 met the inclusion criteria after screening and full-text review.Data extraction focused on study type,country of origin,and oncologic applications of photon-counting CT.No formal risk of bias assessment was performed,and the review was not registered in PROSPERO as it did not include a meta-analysis.RESULTS Key findings highlighted the advantages of PCD CT in imaging renal masses,adrenal adenomas,ovarian cancer,breast cancer,prostate cancer,pancreatic tumors,hepatocellular carcinoma,metastases,multiple myeloma,and lung cancer.Additionally,PCD CT has demonstrated improved lesion characterization and enhanced diagnostic accuracy in oncology.Despite its promising capabilities challenges related to data processing,storage,and accessibility remain.CONCLUSION As PCD CT technology evolves,its integration into routine oncologic imaging has the potential to significantly enhance cancer diagnosis and patient management. 展开更多
关键词 Photon-counting detector CT Oncologic imaging Cancer detection Tumor characterization Spectral imaging Radiology Computed tomography Photon-counting detector CT applications Diagnostic imaging Radiation dose reduction
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Design and optimization of generation and transportation systems for coherent THz transition radiation in spectroscopic applications
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作者 Siriwan Pakluea Kanlayaporn Kongmali +3 位作者 Monchai Jitvisate Jatuporn Saisut Chitrlada Thongbai Sakhorn Rimjaem 《Nuclear Science and Techniques》 2025年第8期34-48,共15页
Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has... Terahertz(THz)radiation possesses unique properties that make it a promising light source for applications in various fields,particularly spectroscopy and imaging.Ongoing research and development in THz technology has focused on developing or improving THz sources,detectors,and applications.At the PBP-CMU Electron Linac Laboratory(PCELL)of the Plasma and Beam Physics Research Facility in Chiang Mai University,high-intensity THz radiation has been generated in the form of coherent transition radiation(TR)and investigated since 2006 for electron beams with energies ranging from 8 to 12 MeV.In this study,we investigate and optimize the coherent TR arising from short electron bunches with energies ranging from 8 to 22 MeV using an upgraded linear-accelerator system with a higher radio-frequency(RF)power system.This radiation is then transported from the accelerator hall to the experimental room,in which the spectrometers are located.Electron-beam simulations are conducted to achieve short bunch lengths and small transverse beam sizes at the TR station.Radiation properties,including the radiation spectrum,angular distribution,and radiation polarization,are thoroughly investigated.The electron-bunch length is evaluated using the measuring system.The radiation-transport line is designed to achieve optimal frequency response and high transmission efficiency.A radiation-transmission efficiency of approximately 80-90%can be achieved with this designed system,along with a pulse energy ranging from 0.17 to 0.25μJ.The expected radiation spectral range covers up to 2 THz with a peak power of 0.5-1.25 MW.This coherent,broadband,and intense THz radiation will serve as a light source for THz spectroscopy and THz time-domain spectroscopy applications at the PCELL in the near future. 展开更多
关键词 THz radiation Transition radiation Radiation transportation
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我国LDR产待一体化护理模式研究新进展
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作者 左兰兰 杨华蓉 《漫科学(新健康)》 2025年第10期150-152,共3页
文章通过综合分析相关文献,阐述了LDR(Labor-Delivery-Recovery)产待一体化护理模式的概念、特点,深入探讨我国实施LDR(Labor-Delivery-Recovery)产待一体化护理模式的优势、应用现状以及面临的挑战,并对其未来发展方向进行了展望,为提... 文章通过综合分析相关文献,阐述了LDR(Labor-Delivery-Recovery)产待一体化护理模式的概念、特点,深入探讨我国实施LDR(Labor-Delivery-Recovery)产待一体化护理模式的优势、应用现状以及面临的挑战,并对其未来发展方向进行了展望,为提升我国产科护理水平,改善产妇分娩体验提供参考依据。 展开更多
关键词 ldr产待一体化 护理模式 初产妇 妊娠结局
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LDR家庭化一站式产房精选中医特色项目的实践观察
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作者 季玲 马丹 《中医药管理杂志》 2025年第12期158-160,共3页
目的:探讨和分析LDR家庭化一站式产房精选中医特色项目的实践观察效果,提高产房产妇的护理水平。方法:选取医院2023年1月—2024年4月的167名产科产妇为调查对象,分为对照组82名和观察组85名。对照组给予常规护理方案干预,观察组给予LDR... 目的:探讨和分析LDR家庭化一站式产房精选中医特色项目的实践观察效果,提高产房产妇的护理水平。方法:选取医院2023年1月—2024年4月的167名产科产妇为调查对象,分为对照组82名和观察组85名。对照组给予常规护理方案干预,观察组给予LDR家庭化一站式产房精选中医特色项目方案干预。比较两组管理效果。结果:观察组分娩结局指标发生率低于对照组(P<0.05)。观察组新生儿Apgar评分分级情况优于对照组(P<0.05)。观察组并发症发生率为3.53%,低于对照组14.63%(P<0.05)。结论:LDR家庭化一站式产房精选中医特色项目实践效果显著,该模式能够提高产科产妇的健康状况,并且在分娩过程中减少新生儿窘迫以及术后出血情况,改善分娩结局。 展开更多
关键词 ldr家庭化 一站式产房 精选中医特色项目 实践观察效果
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LDR产房导乐陪伴联合自由体位分娩助产技术对初产妇的应用价值探讨
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作者 成茜洋 《健康导刊》 2025年第24期85-87,共3页
目的探讨LDR产房导乐陪伴与自由体位分娩助产技术对初产妇的联合应用效果。方法2023年1-6月,择取于该院就医的经阴道分娩初产妇160例,经随机数字表法分为对照组(常规分娩助产技术,n=80)和实验组(LDR产房导乐陪伴+自由体位分娩助产技术,n... 目的探讨LDR产房导乐陪伴与自由体位分娩助产技术对初产妇的联合应用效果。方法2023年1-6月,择取于该院就医的经阴道分娩初产妇160例,经随机数字表法分为对照组(常规分娩助产技术,n=80)和实验组(LDR产房导乐陪伴+自由体位分娩助产技术,n=80)。比较两组产妇产程用时、不良分娩结局发生率、新生儿不良结局发生率、产妇焦虑及抑郁评分、产妇护理满意度。结果实验组各产程用时均短于对照组(P<0.05)。实验组产妇不良分娩结局发生率低于对照组(P<0.05)。实验组新生儿不良结局发生率低于对照组(P<0.05)。分娩前,两组产妇焦虑、抑郁评分比较无显著差异(P>0.05);分娩后,相较于对照组,实验组产妇焦虑、抑郁评分均降低(P<0.05)。实验组产妇护理总满意率高于对照组(P<0.05)。结论在初产妇阴道分娩中,联合应用LDR产房导乐陪伴与自由体位分娩助产技术,较常规助产技术能有效缩短各产程时间,降低母婴不良结局的发生风险,减轻产妇产后的焦虑与抑郁情绪,并提升产妇对护理服务的满意度。 展开更多
关键词 自由体位分娩助产技术 ldr产房导乐陪伴 常规分娩助产技术
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Impact of Window-to-Wall Ratio on Thermal Comfort and Energy Performance of Hybrid Cooling Systems
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作者 Dong Liu Runze Zhang +4 位作者 Anjie Hu Na Liu Liu Tang Xiaozhou Wu Jun Wang 《Fluid Dynamics & Materials Processing》 2025年第10期2579-2612,共34页
This study compares two end-cooling systems,convective-radiant combined cooling(FR+FC)and fan coil convection(FC),through continuous experimental investigations,focusing on the impact of window-to-wall ratio(WWR)on in... This study compares two end-cooling systems,convective-radiant combined cooling(FR+FC)and fan coil convection(FC),through continuous experimental investigations,focusing on the impact of window-to-wall ratio(WWR)on indoor thermal comfort,temperature distribution,humidity,and energy consumption.Results show that increasing WWR amplifies indoor temperature fluctuations.While the overall predicted mean vote(PMV)remains within the Level-II comfort range(−1.0 to+1.0),the FC system exhibits pronounced local PMV gradients near west-facing windows,especially at 80%WWR,where transient PMV reaches 1.26 close to the window,0.89 higher than at the room center.In contrast,the FR+FC system significantly reduces spatial PMV variations,maintaining local PMV within acceptable limits for most of the day.Energy analysis reveals that FC energy consumption rises with WWR,increasing by 7.11%from 40%to 80%WWR,whereas FR+FC energy use decreases by 29.26%over the same range,demonstrating its superior handling of radiant loads.Furthermore,the convective-radiant system exhibits a high average hourly cooling performance coefficient.These findings indicate that FR+FC systems provide better thermal comfort and energy efficiency in high-WWR spaces,making them particularly suitable for summer operation in window-intensive buildings. 展开更多
关键词 Window-to-wall ratio solar radiation thermal comfort energy consumption
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Prediction of Daily Global Solar Radiation on a Horizontal Plane Using Adaptive Neuro-Fuzzy Inference System(ANFIS)
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作者 Hamatti Mohamed Benchrifa Mohammed +4 位作者 Mohamed Elouardi Mouhsine Hadine Mabrouki Jamal El-Baz Morad Tadili Rachid 《Journal of Environmental & Earth Sciences》 2025年第1期527-539,共13页
In recent years,the world has seen an exponential increase in energy demand,prompting scientists to look for innovative ways to exploit the power sun’s power.Solar energy technologies use the sun’s energy and light ... In recent years,the world has seen an exponential increase in energy demand,prompting scientists to look for innovative ways to exploit the power sun’s power.Solar energy technologies use the sun’s energy and light to provide heating,lighting,hot water,electricity and even cooling for homes,businesses,and industries.Therefore,ground-level solar radiation data is important for these applications.Thus,our work aims to use a mathematical modeling tool to predict solar irradiation.For this purpose,we are interested in the application of the Adaptive Neuro Fuzzy Inference System.Through this type of artificial neural system,10 models were developed,based on meteorological data such as the Day number(Nj),Ambient temperature(T),Relative Humidity(Hr),Wind speed(WS),Wind direction(WD),Declination(δ),Irradiation outside the atmosphere(Goh),Maximum temperature(Tmax),Minimum temperature(Tmin).These models have been tested by different static indicators to choose the most suitable one for the estimation of the daily global solar radiation.This study led us to choose the M8 model,which takes Nj,T,Hr,δ,Ws,Wd,G0,and S0 as input variables because it presents the best performance either in the learning phase(R^(2)=0.981,RMSE=0.107 kW/m^(2),MAE=0.089 kW/m2)or in the validation phase(R^(2)=0.979,RMSE=0.117 kW/m^(2),MAE=0.101 kW/m^(2)). 展开更多
关键词 Solar Radiation Adaptive Neuro-Fuzzy Inference system Prediction Horizontal Plane Mathematical Modelling
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Integrated infrared and radar stealth optimization for the exhaust system of UCAV using multi-fidelity data fusion and Bayesian optimization
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作者 Saile ZHANG Yongqiang SHI +1 位作者 Qingzhen YANG Rui WANG 《Chinese Journal of Aeronautics》 2025年第7期507-528,共22页
The resource-intensive,high-fidelity infrared signature simulations and Radar CrossSection(RCS)calculations limit the integrated optimization of Unmanned Combat Aerial Vehicles(UCAVs)in response to escalating threats ... The resource-intensive,high-fidelity infrared signature simulations and Radar CrossSection(RCS)calculations limit the integrated optimization of Unmanned Combat Aerial Vehicles(UCAVs)in response to escalating threats from joint detection systems.To this end,we present a sample-efficient framework to advance the optimization efficiency of UCAV's exhaust system,focusing on both the stealth characteristics evaluation and the optimization process.A novel multi-fidelity stealth assessment method,powered by multi-fidelity neural network and local perceptive fields,has been developed to fuse different fidelity information from infrared radiation signature and RCS values,respectively.Results demonstrate that the method can achieve relatively high accuracy based on a small set of high-fidelity data.Furthermore,this data fusion method is integrated into a multi-objective Bayesian optimization framework.Employing a Gaussian process regression model and the EHVI acquisition function,the framework effectively explores the stealth objective space,achieving a 15.21%hypervolume indicator increase with fewer optimization iterations compared to NSGA-Ⅱ.Results show that the optimized nozzle significantly reduces both the infrared signature and RCS compared to the baseline configuration.The proposed framework offers a practical and efficient approach for optimizing the integrated stealth performance of UCAVs. 展开更多
关键词 Infrared radiation Radar cross-section Multi-fidelity Double serpentine nozzle Multi-objective stealth optimization
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Transjugular intrahepatic portosystemic shunt creation using intravascular ultrasound vs fluoroscopic guidance:A dual-institution retrospective comparative study
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作者 Matthew L Hung Abhishek Jairam +8 位作者 Matthew Carr Zachary T Berman Michael Taddonio Jeet Minocha Hamed Aryafar Jeffrey I Mondschein Michael C Soulen Gregory J Nadolski Jonas Redmond 《World Journal of Hepatology》 2025年第5期132-139,共8页
BACKGROUND The use of intravascular ultrasound(iUS)has been shown in multiple singlecenter retrospective studies to decrease procedure time,radiation exposure,and needle passes compared to conventional fluoroscopic gu... BACKGROUND The use of intravascular ultrasound(iUS)has been shown in multiple singlecenter retrospective studies to decrease procedure time,radiation exposure,and needle passes compared to conventional fluoroscopic guidance in the creation of a transjugular intrahepatic portosystemic shunt(TIPS).However,there are few data regarding the impact of imaging guidance modality choice on clinical outcomes.AIM To determine the impact of iUS vs fluoroscopic guidance during creation of a TIPS on procedural metrics,liver injury,shunt patency and mortality.METHODS The retrospective study cohort consisted of 66 patients who underwent TIPS creation using iUS[“iUS-guided TIPS(iTIPS)group”]and 135 patients who underwent TIPS creation using fluoroscopic guidance[“conventional fluoroscopic-guided TIPS(cTIPS)group”]at 2 tertiary academic medical centers from 2015-2019.TIPS that required variceal embolization or portal vein recanalization were excluded.RESULTS The technical success rate was 100%in the iTIPS group and 96%in the cTIPS group(P=0.17).The iTIPS group had an air kerma(266±254 mGy vs 1235±1049 mGy,P<0.00001),dose area product(5728±6518 uGy×m^(2) vs 28969±19067 uGy×m^(2),P<0.00001),fluoroscopy time(18.7±9.6 minutes vs 32.3±19.0 minutes,P<0.00001),and total procedure time(93±40 minutes vs 110±51 minutes,P=0.01)which were significantly lower than the cTIPS group.There was no significant difference in liver function test adverse event grade at 1 month.With a median follow-up of 26 months(inter quartile range:6-61 months),there was no difference between the two groups in terms of thrombosis-free survival(P=0.23),intervention-free survival(P=0.29),or patient mortality(P=0.61).CONCLUSION The use of iUS in the creation of TIPS reduces radiation exposure and procedure time compared with fluoroscopic guidance.At midterm follow-up,the imaging guidance modality did not affect shunt patency or mortality. 展开更多
关键词 Portal hypertension Transjugular intrahepatic portosystemic shunt Radiation Intravascular ultrasound Shunt patency
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A fast configuration method for external cooling system of power transformer considering energy loss
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作者 Lujia Wang Mengzhi Sun +2 位作者 Zhenlu Cai Haitao Yang Xibo Wu 《iEnergy》 2025年第4期269-277,共9页
Radiator cooling configurations need to account for both efficient heat dissipation and energy conservation requirements.Rapid and rational determination of cooling system configurations constitutes a critical aspect ... Radiator cooling configurations need to account for both efficient heat dissipation and energy conservation requirements.Rapid and rational determination of cooling system configurations constitutes a critical aspect of transformer design,enhancing electrical power energy utilization efficiency.Computational fluid dynamics(CFD)is widely recognized as a well-established technique for simulating and optimizing heat dissipation systems.However,this approach is time-consuming because of pre-processing procedures,such as meshing.This paper proposes a fast iterative optimization model for calculating the outlet oil temperature and airflow distribution.Based on the analytical model results,this paper identifies the optimal energy-saving range for radiator cooling configurations,incorporating the cooperative effects of cooling efficiency,air pressure drop during heat transfer,and inlet–outlet temperature difference.The analytical model demonstrated errors in energy dissipation and temperature difference calculations within an acceptable range.The calculation time was reduced by more than 99%.Radiator configurations within the optimal range effectively minimize energy waste while meeting the target temperature difference and enhancing cooling efficiency.Finally,the PC2600-22/520 radiator was utilized to validate the accuracy of the analytical model and the rationality of the co-optimal intervals. 展开更多
关键词 Power transformer oil temperature difference radiator thermal efficiency air pressure drop
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A Review of the Applications of Nanofluids and Related Hybrid Variants in Flat Tube Car Radiators
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作者 Saeed Dinarvand Amirmohammad Abbasi Sogol Gharsi 《Fluid Dynamics & Materials Processing》 2025年第1期37-60,共24页
The present review explores the promising role of nanofluids and related hybrid variants in enhancing the efficiencyof flat tube car radiators.As vehicles become more advanced and demand better thermal performance,tra... The present review explores the promising role of nanofluids and related hybrid variants in enhancing the efficiencyof flat tube car radiators.As vehicles become more advanced and demand better thermal performance,traditional coolants are starting to fall short.Nanofluids,which involve tiny nanoparticles dispersed into standardcooling liquids,offer a new solution by significantly improving heat transfer capabilities.The article categorizesthe different types of nanofluids(ranging from those based on metals and metal oxides to carbon materials andhybrid combinations)and examines their effects on the improvement of radiator performance.General consensusexists in the literature that nanofluids can support better heat dissipation and enable accordingly the developmentof smaller and lighter radiators,which require less coolant and allow more compact vehicle designs.However,thisreview demonstrates that the use of nanofluids does not come without challenges.These include the long-termstability of these fluids and material compatibility issues.A critical discussion is therefore elaborated about thegaps to be filled and the steps to be undertaken to promote and standardize the use of these fluids in the industry. 展开更多
关键词 Flat tube car radiator nano-coolant stability metal-based nanoparticle heat transfer enhancement ethylene glycol
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掺镱光纤激光器伽马辐照响应特性
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作者 陶蒙蒙 谌鸿伟 +6 位作者 王亚民 王科 邵冲云 李哲 李生武 李乔木 叶景峰 《物理学报》 北大核心 2026年第3期185-194,共10页
光纤激光器在太空、反应堆、大型加速器等辐射环境中应用时,辐射与光纤的相互作用会给光纤参数带来较大变化,从而影响激光器的输出性能.本文对掺镱光纤激光器的伽马辐照响应特性开展了实验和仿真研究.实验对比了无源光纤、泵浦合束器、... 光纤激光器在太空、反应堆、大型加速器等辐射环境中应用时,辐射与光纤的相互作用会给光纤参数带来较大变化,从而影响激光器的输出性能.本文对掺镱光纤激光器的伽马辐照响应特性开展了实验和仿真研究.实验对比了无源光纤、泵浦合束器、光纤光栅、增益光纤等不同光纤器件在辐照环境下的性能变化,通过对比分析明确了增益光纤是激光器系统中对辐射最为敏感的光纤器件.实验研究了泵浦方式、增益光纤长度对掺镱光纤激光器辐射响应特性的影响,并通过理论模拟对实验结果进行了分析验证;结果表明,后向泵浦方式和更短的增益光纤有助于降低光纤激光器系统的辐射敏感性.相关研究结果可为光纤激光器抗辐射优化设计提供技术参考,支撑激光器在辐射环境中的安全使用. 展开更多
关键词 辐致损耗 掺镱光纤激光器 伽马辐照
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中国大陆Himawari-9短波辐射数据适用性研究
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作者 黄洋 李翠娜 +3 位作者 汪翔 戴铁 石锐 孙豪 《太阳能学报》 北大核心 2026年第2期235-243,共9页
利用2023年中国136个辐射站逐小时总辐射对Himawari-9短波辐射进行多时空尺度评估,结果表明:1)全国平均日内变化上,08:00—18:00期间Himawari-9短波辐射与地基总辐射的相关系数(Corr)均超过0.85,呈单峰型分布,09:00和10:00最高;均方根误... 利用2023年中国136个辐射站逐小时总辐射对Himawari-9短波辐射进行多时空尺度评估,结果表明:1)全国平均日内变化上,08:00—18:00期间Himawari-9短波辐射与地基总辐射的相关系数(Corr)均超过0.85,呈单峰型分布,09:00和10:00最高;均方根误差(RMSE)日内变化同样呈单峰型分布,15:00最高;平均偏差(Bias)呈双峰型分布,峰值分别出现在10:00和15:00。2)全国平均年内变化上,Corr呈双峰型分布,两个峰值分别出现在4和10月份;RMSE呈单峰型分布,夏季(7—8月份)最高,均超过了100 W/m^(2),秋冬季节的RMSE较低;Bias为单峰型分布,春季最高,12月份Bias最低。3)空间分布上,中国中部和东部地区的Corr较高,北方和高原地区部分站点的Corr较低;中部和东部地区为RMSE低值区,这些区域Himawari-9短波辐射高于地基总辐射,西部、北部和高原地区为RMSE高值区,Himawari-9短波辐射低于地基总辐射。4)进一步分析海拔高度对Himawari-9短波辐射质量的影响,整体上随海拔高度增加,Corr减小,RMSE增大,在海拔高度低于2000 m的地区Himawari-9短波辐射整体高于地基总辐射,高于2000 m的地区Himawari-9短波辐射存在对低辐照度高估、对高辐照度低估的特征;通过不同卫星仰角分组评估表明,在中低海拔地区,RMSE呈单谷型分布,仰角在20°~25°时,RMSE最低,仰角低于20°时,Bias为负值,随仰角增加,Bias转为正值并逐渐增大,高海拔地区在仰角低于35°时,评估结果差异较小,仰角大于35°,Corr最低,RMSE最高。 展开更多
关键词 Himawari-9 短波辐射 辐射评估 相关性分析 系统偏差
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乳腺癌保乳术中放疗隔离技术标准作业流程实施效果评价
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作者 何璐 黄朝意 +1 位作者 林慧宏 曾洋帆 《护理学杂志》 北大核心 2026年第1期66-71,共6页
目的探讨乳腺癌保乳术中放疗隔离技术操作标准作业流程的实施效果,为提高乳腺癌保乳术中放疗隔离技术操作质量提供参考。方法选取接受乳腺癌保乳术中放疗的240例患者为研究对象,按照手术时间分为试验组和对照组各120例。对照组实施常规... 目的探讨乳腺癌保乳术中放疗隔离技术操作标准作业流程的实施效果,为提高乳腺癌保乳术中放疗隔离技术操作质量提供参考。方法选取接受乳腺癌保乳术中放疗的240例患者为研究对象,按照手术时间分为试验组和对照组各120例。对照组实施常规隔离技术操作,试验组在对照组的基础上实施标准作业流程管理。结果试验组手术室护士隔离技术操作总分(91.08±2.89)显著高于对照组(89.14±2.90),试验组术后1个月、3个月放射性皮炎发生率显著低于对照组(均P<0.05);试验组手术间平均辐射剂量和医护人员平均累积剂量显著低于对照组(均P<0.05)。结论标准作业流程用于乳腺癌保乳术中放疗隔离技术操作,能够显著提高医护人员隔离技术操作规范性,降低患者术后放射性皮炎发生率及医护人员辐射暴露。 展开更多
关键词 乳腺癌 保乳术 术中放疗 隔离技术 标准作业流程 放射性皮炎 辐射剂量 手术室护理
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CCD抗辐射加固技术研究进展
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作者 王祖军 蒋镕羽 +3 位作者 王盆生 陈明雷 杨鑫 李传洲 《半导体光电》 北大核心 2026年第1期1-12,共12页
电荷耦合器件(CCD)在探测和成像领域应用广泛,然而其在辐射环境中应用时会遭受辐照损伤的影响。为提升CCD抗辐射性能,国内外已开展大量的抗辐射加固技术研究。文章主要从信号转移沟道设计、栅氧工艺设计、栅极工艺设计、片上放大器及读... 电荷耦合器件(CCD)在探测和成像领域应用广泛,然而其在辐射环境中应用时会遭受辐照损伤的影响。为提升CCD抗辐射性能,国内外已开展大量的抗辐射加固技术研究。文章主要从信号转移沟道设计、栅氧工艺设计、栅极工艺设计、片上放大器及读出电路抗辐射加固设计等方面综述了CCD在工艺结构方面的抗辐射加固技术研究进展;从多相钳位工作模式、电荷注入工作模式、低温工作模式、时钟驱动优化工作模式等方面综述了CCD在工作模式方面的抗辐射加固技术研究进展;此外,还介绍了CCD从图像校正、辐射屏蔽等方面的抗辐射加固技术研究进展。相关研究为开展CCD抗辐射加固设计提供了实验依据和理论基础。 展开更多
关键词 电荷耦合器件 抗辐射加固 辐照损伤效应 辐射敏感参数
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