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Multi-Scale Feature Fusion and Advanced Representation Learning for Multi Label Image Classification
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作者 Naikang Zhong Xiao Lin +1 位作者 Wen Du Jin Shi 《Computers, Materials & Continua》 2025年第3期5285-5306,共22页
Multi-label image classification is a challenging task due to the diverse sizes and complex backgrounds of objects in images.Obtaining class-specific precise representations at different scales is a key aspect of feat... Multi-label image classification is a challenging task due to the diverse sizes and complex backgrounds of objects in images.Obtaining class-specific precise representations at different scales is a key aspect of feature representation.However,existing methods often rely on the single-scale deep feature,neglecting shallow and deeper layer features,which poses challenges when predicting objects of varying scales within the same image.Although some studies have explored multi-scale features,they rarely address the flow of information between scales or efficiently obtain class-specific precise representations for features at different scales.To address these issues,we propose a two-stage,three-branch Transformer-based framework.The first stage incorporates multi-scale image feature extraction and hierarchical scale attention.This design enables the model to consider objects at various scales while enhancing the flow of information across different feature scales,improving the model’s generalization to diverse object scales.The second stage includes a global feature enhancement module and a region selection module.The global feature enhancement module strengthens interconnections between different image regions,mitigating the issue of incomplete represen-tations,while the region selection module models the cross-modal relationships between image features and labels.Together,these components enable the efficient acquisition of class-specific precise feature representations.Extensive experiments on public datasets,including COCO2014,VOC2007,and VOC2012,demonstrate the effectiveness of our proposed method.Our approach achieves consistent performance gains of 0.3%,0.4%,and 0.2%over state-of-the-art methods on the three datasets,respectively.These results validate the reliability and superiority of our approach for multi-label image classification. 展开更多
关键词 Image classification MULTI-LABEL multi scale attention mechanisms feature fusion
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Impacts of lateral boundary conditions from numerical models and data-driven networks on convective-scale ensemble forecasts
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作者 Junjie Deng Jin Zhang +3 位作者 Haoyan Liu Hongqi Li Feng Chen Jing Chen 《Atmospheric and Oceanic Science Letters》 2025年第2期78-85,共8页
The impacts of lateral boundary conditions(LBCs)provided by numerical models and data-driven networks on convective-scale ensemble forecasts are investigated in this study.Four experiments are conducted on the Hangzho... The impacts of lateral boundary conditions(LBCs)provided by numerical models and data-driven networks on convective-scale ensemble forecasts are investigated in this study.Four experiments are conducted on the Hangzhou RDP(19th Hangzhou Asian Games Research Development Project on Convective-scale Ensemble Prediction and Application)testbed,with the LBCs respectively sourced from National Centers for Environmental Prediction(NCEP)Global Forecast System(GFS)forecasts with 33 vertical levels(Exp_GFS),Pangu forecasts with 13 vertical levels(Exp_Pangu),Fuxi forecasts with 13 vertical levels(Exp_Fuxi),and NCEP GFS forecasts with the vertical levels reduced to 13(the same as those of Exp_Pangu and Exp_Fuxi)(Exp_GFSRDV).In general,Exp_Pangu performs comparably to Exp_GFS,while Exp_Fuxi shows slightly inferior performance compared to Exp_Pangu,possibly due to its less accurate large-scale predictions.Therefore,the ability of using data-driven networks to efficiently provide LBCs for convective-scale ensemble forecasts has been demonstrated.Moreover,Exp_GFSRDV has the worst convective-scale forecasts among the four experiments,which indicates the potential improvement of using data-driven networks for LBCs by increasing the vertical levels of the networks.However,the ensemble spread of the four experiments barely increases with lead time.Thus,each experiment has insufficient ensemble spread to present realistic forecast uncertainties,which will be investigated in a future study. 展开更多
关键词 Ensemble forecast Convective scale Lateral boundary conditions Data-driven network
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Development and validation of the Chinese version of the Clinician-reported submental fat rating scale
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作者 Yuming Chong Yilin Li +5 位作者 Xiaojun Wang Nanze Yu Jiuzuo Huang Hairu Cao Wenyun Ting Xiao Long 《Chinese Journal of Plastic and Reconstructive Surgery》 2025年第1期1-4,共4页
Background:Excess submental fat(SMF)is a common facial aesthetic concern,and assessment scales play a crucial role in its evaluation.Existing SMF scales are based on Caucasian populations,although genetic background s... Background:Excess submental fat(SMF)is a common facial aesthetic concern,and assessment scales play a crucial role in its evaluation.Existing SMF scales are based on Caucasian populations,although genetic background significantly influences SMF distribution.Therefore,this study aimed to develop and validate a 5-point Chinese version of the Clinician-Reported Submental Fat Rating Scale(CR-SMFRS).Methods:The study included 150 volunteers,and captured photographs from the frontal,oblique,and lateral views were combined for each participant.A 5-point scale with descriptive criteria was primarily designed.Internal validation involved three experienced plastic surgeons,while external validation was conducted on 50 live volunteers by six additional raters.Intra-and inter-rater reliability were assessed.Results:A 5-point grading system with descriptive criteria was developed and validated as the Chinese CR-SMFRS.Internal validation demonstrated a good intra-and inter-rater consistency.During external validation,intraclass correlation coefficient values for each rater exceeded 0.850,indicating high intra-rater consistency.Moreover,the inter-rater reliability showed good consistency.Conclusion:The Chinese version of the SMF rating scale is a reliable tool for clinical use. 展开更多
关键词 Submental fat Photonumeric scale Aesthetic medicine
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Stable computations of the spherically layered media theory with high lossy media by using scaled Bessel functions
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作者 Jia-Hui Wang Bo O.Zhu 《Journal of Electronic Science and Technology》 2025年第1期22-34,共13页
The spherically layered media theory has wide applications for electromagnetic wave scattering analysis.Due to the involved Bessel functions,the conventional formulations of spherically layered media theory suffer fro... The spherically layered media theory has wide applications for electromagnetic wave scattering analysis.Due to the involved Bessel functions,the conventional formulations of spherically layered media theory suffer from numerical overflow or underflow when the Bessel function’s order is large,the argument is small or the argument has a large imaginary part.The first two issues have been solved recently by employing small-argument asymptotic formulas of Bessel functions,while the third issue remains unsolved.In this paper,the Bessel functions in the conventional formulation of the theory are replaced by scaled Bessel functions which have good numerical properties for high loss media,and stable formulas are derived.Numerical tests show that this approach can work properly with very high lossy media.Also,this approach can be seamlessly combined with the stable computation method for cases of small argument and large order of Bessel functions. 展开更多
关键词 Lossy media Numerical stability scaled Bessel function Spherically layered media theory
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Cultural Adaptation of the Mental Health Literacy Scale
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作者 Anwar Khatib Avital Laufer +1 位作者 Michal Finkelstein Marc Gelkopf 《International Journal of Mental Health Promotion》 2025年第1期19-28,共10页
Background:Mental health literacy(MHL)refers to one’s knowledge and understanding of mental health disorders and their treatments.This literacy may be influenced by cultural norms and values that shape individuals’e... Background:Mental health literacy(MHL)refers to one’s knowledge and understanding of mental health disorders and their treatments.This literacy may be influenced by cultural norms and values that shape individuals’experiences,beliefs,attitudes,and behaviors regarding mental health.This study focuses on adapting the Mental health literacy scale(MHLS)for use in the multicultural context of Israel.Objectives include validating its construct,assessing its accuracy in measuring MHL in this diverse setting and examining and comparing levels of MHL across different cultural groups.Methods:The data collection included 1057 participants,representing all the ethnic groups of the Israeli population aged 18 and over.The tools included the MHLS and a demographic questionnaire.Confirmatory factor analysis(CFA)was employed to assess the original structure of the MHLS.Results:The results revealed that after evaluating the original MHLS,five items were excluded,leading to the validation of a modified version—Israeli mental health scale(IMHLS)with four factors and 25 items.CFA and reliability analyses supported an established and robust four-factor model.Significant ethnic differences in MHLS scores were identified,with Muslim participants showing the highest familiarity with mental disorders,followed by Druze and Christian participants,while Jewish participants had the lowest familiarity.Conclusion:The study concluded that the IMHLS is a valid and reliable tool for assessing MHL in Israel’s diverse and multicultural population.The revised scale better reflects the cultural nuances of the Israeli context.The significant ethnic differences that the study revealed in IMHLS emphasize the importance of culturally sensitive mental health interventions tailored to different ethnic groups in Israel. 展开更多
关键词 Cultural adaptation mental health literacy scale multicultural society
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A complementary approach to quantify the basic GSI chart considering scale effect on rock structure
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作者 Harun Sonmez Gulseren Dagdelenler +1 位作者 Yilmaz Ozcelik Murat Ercanoglu 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第1期154-167,共14页
Geological strength index(GSI)has been widely used as an input parameter in predicting the strength and deformation properties of rock masses.This study derived a series of equations to satisfy the original GSI lines ... Geological strength index(GSI)has been widely used as an input parameter in predicting the strength and deformation properties of rock masses.This study derived a series of equations to satisfy the original GSI lines on the basic GSI chart.Two axes ranging from 0 to 100 were employed for surface conditions of the discontinuities and the structure of rock mass,which are independent of the input parameters.The derived equations can analyze GSI values ranging from 0 to 100 within±5%error.The engineering dimensions(EDs)such as the slope height,tunnel width,and foundation width were used together with representative elementary volume(REV)in jointed rock mass to define scale factor(sf)from 0.2 to 1 in evaluating the rock mass structure including joint pattern.The transformation of GSI into a scaledependent parameter based on engineering scale addresses a crucial requirement in various engineering applications.The improvements proposed in this study were applied to a real slope which was close to the time of failure.The results of stability assessments show that the new proposals have sufficient capability to define rock mass quality considering EDs. 展开更多
关键词 Basic GSI chart Engineering dimension(ED) Hoek and Brown failure criterion Quantification of GSI Quantitative GSI chart scale effect
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Small-Scale Irrigation in the Highlands of Western Cameroon: A Diagnostic Study of the Southern Slope of the Bamboutos Mountains
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作者 Sibelle Tsague Mouafo Nasse Fetio Ngoune +1 位作者 Roger Ntankouo Njila Barthelemy Ndongo 《Agricultural Sciences》 2025年第2期256-279,共24页
Irrigated agriculture in Cameroon is practiced on a large scale by large private firms and parastatals, and on a small scale by individual producers in different production areas of the country. Although small-scale i... Irrigated agriculture in Cameroon is practiced on a large scale by large private firms and parastatals, and on a small scale by individual producers in different production areas of the country. Although small-scale irrigation can supply local and sub-regional markets with food in the off-season, it has received little research and its challenges are therefore rarely addressed. In order to contribute to the knowledge of these small-scale irrigation systems, with a view to improving their structure and the management of irrigation water and energy, an assessment of small-scale irrigation in the southern slopes of the Bamboutos Mountains has been done. After direct observations, field measurements, surveys of 100 irrigators with questionnaires and interviews with administrative managers, analyses were carried out using Xlstat software. It was found out that about 226 small-scale irrigation systems designed and managed by producers have been installed on this slope between the end of December 2022 and mid-March 2023. Intended for market garden crops, 84.96% of these irrigation systems use sprinklers and 15.04% surface irrigation (furrow irrigation). Surface or underground water is mobilized using gravity (50%), fossil fuels (34.51%), electricity (14.6%) or solar energy (0.9%). Sprinkler irrigation is mainly carried out using locally manufactured hydraulic turnstiles. There is a lack of formal associations of irrigators in an environment marked by conflicts between water users, when there is not allocation for water withdrawal. Apart from the high cost of pumping energy ($1.32 per liter of fuel), the main constraint identified, which has become more acute over the years, is the lack of irrigation water during the water shortage period (from mid-January to mid-March). These constraints have led to a transition from surface irrigation to sprinkler irrigation, and the adoption of new energy supply and water mobilization technologies. The construction of collective surface and groundwater catchment structures with solar-powered pumping systems, the setting up of formal irrigators’ associations and an irrigation support service, could improve the availability of water throughout the irrigation season, thereby helping to improve the income generated by irrigated market-garden farming on the southern slopes of the Bamboutos Mountains. 展开更多
关键词 Market Gardening Water Energy Small-scale Irrigation Southern Slope of the Bamboutos Mountains
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Scale-space effect and scale hybridization in image intelligent recognition of geological discontinuities on rock slopes 被引量:1
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作者 Mingyang Wang Enzhi Wang +1 位作者 Xiaoli Liu Congcong Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1315-1336,共22页
Geological discontinuity(GD)plays a pivotal role in determining the catastrophic mechanical failure of jointed rock masses.Accurate and efficient acquisition of GD networks is essential for characterizing and understa... Geological discontinuity(GD)plays a pivotal role in determining the catastrophic mechanical failure of jointed rock masses.Accurate and efficient acquisition of GD networks is essential for characterizing and understanding the progressive damage mechanisms of slopes based on monitoring image data.Inspired by recent advances in computer vision,deep learning(DL)models have been widely utilized for image-based fracture identification.The multi-scale characteristics,image resolution and annotation quality of images will cause a scale-space effect(SSE)that makes features indistinguishable from noise,directly affecting the accuracy.However,this effect has not received adequate attention.Herein,we try to address this gap by collecting slope images at various proportional scales and constructing multi-scale datasets using image processing techniques.Next,we quantify the intensity of feature signals using metrics such as peak signal-to-noise ratio(PSNR)and structural similarity(SSIM).Combining these metrics with the scale-space theory,we investigate the influence of the SSE on the differentiation of multi-scale features and the accuracy of recognition.It is found that augmenting the image's detail capacity does not always yield benefits for vision-based recognition models.In light of these observations,we propose a scale hybridization approach based on the diffusion mechanism of scale-space representation.The results show that scale hybridization strengthens the tolerance of multi-scale feature recognition under complex environmental noise interference and significantly enhances the recognition accuracy of GD.It also facilitates the objective understanding,description and analysis of the rock behavior and stability of slopes from the perspective of image data. 展开更多
关键词 Image processing Geological discontinuities Deep learning MULTI-scale scale-space theory scale hybridization
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Multi-scale design of silicon/carbon composite anode materials for lithium-ion batteries:A review 被引量:1
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作者 Liu Yang Shuaining Li +6 位作者 Yuming Zhang Hongbo Feng Jiangpeng Li Xinyu Zhang Huai Guan Long Kong Zhaohui Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期30-45,I0002,共17页
Silicon/carbon composites,which integrate the high lithium storage performance of silicon with the exceptional mechanical strength and conductivity of carbon,will replace the traditional graphite electrodes for high-e... Silicon/carbon composites,which integrate the high lithium storage performance of silicon with the exceptional mechanical strength and conductivity of carbon,will replace the traditional graphite electrodes for high-energy lithium-ion batteries.Various strategies have been designed to synthesize silicon/carbon composites for tackling the issues of anode pulverization and poor stability in the anodes,thereby improving the lithium storage ability.The effect of the regulation method at each scale on the final negative electrode performance remains unclear.However,it has not been fully clarified how the regulation methods at each scale influence the final anode performance.This review will categorize the materials structure into three scales:molecular scale,nanoscale,and microscale.First,the review will examine modification methods at the molecular scale,focusing on the interfacial bonding force between silicon and carbon.Next,it will summarize various nanostructures and special shapes in the nanoscale to explore the construction of silicon/carbon composites.Lastly,the review will provide an analysis of microscale control approaches,focusing on the formation of composite particle with micron size and the utilization of micro-Si.This review provides a comprehensive overview of the multi-scale design of silicon/carbon composite anode materials and their optimization strategies to enhance the performance of lithium-ion batteries. 展开更多
关键词 Lithium-ion batteries Silicon/carbon composites Molecular scale Nanoscale MICROscale
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Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale 被引量:1
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作者 Kamolthip Ruckwongpatr Chirawat Paratthakonkun +8 位作者 Usanut Sangtongdee Iqbal Pramukti Ira Nurmala Kanokwan Angkasith Weena Thanachaisakul Jatuphum Ketchatturat Mark DGriffiths Yi-Kai Kao Chung-Ying Lin 《International Journal of Mental Health Promotion》 2024年第4期293-302,共10页
Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,t... Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in Thailand.The present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor structure.Findings demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across genders.Moreover,scores on the SABAS and BSMAS were correlated with scores on the IGDS9-SF.Conclusion:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults. 展开更多
关键词 Factor analysis smartphone addiction social media addiction smartphone application-based addiction scale bergen social media addiction scale psychometric validation
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Uncertainties of landslide susceptibility prediction:influences of different study area scales and mapping unit scales
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作者 Faming Huang Yu Cao +4 位作者 Wenbin Li Filippo Catani Guquan Song Jinsong Huang Changshi Yu 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期143-172,共30页
This study aims to investigate the effects of different mapping unit scales and study area scales on the uncertainty rules of landslide susceptibility prediction(LSP).To illustrate various study area scales,Ganzhou Ci... This study aims to investigate the effects of different mapping unit scales and study area scales on the uncertainty rules of landslide susceptibility prediction(LSP).To illustrate various study area scales,Ganzhou City in China,its eastern region(Ganzhou East),and Ruijin County in Ganzhou East were chosen.Different mapping unit scales are represented by grid units with spatial resolution of 30 and 60 m,as well as slope units that were extracted by multi-scale segmentation method.The 3855 landslide locations and 21 typical environmental factors in Ganzhou City are first determined to create spatial datasets with input-outputs.Then,landslide susceptibility maps(LSMs)of Ganzhou City,Ganzhou East and Ruijin County are pro-duced using a support vector machine(SVM)and random forest(RF),respectively.The LSMs of the above three regions are then extracted by mask from the LSM of Ganzhou City,along with the LSMs of Ruijin County from Ganzhou East.Additionally,LSMs of Ruijin at various mapping unit scales are generated in accordance.Accuracy and landslide suscepti-bility indexes(LSIs)distribution are used to express LSP uncertainties.The LSP uncertainties under grid units significantly decrease as study area scales decrease from Ganzhou City,Ganzhou East to Ruijin County,whereas those under slope units are less affected by study area scales.Of course,attentions should also be paid to the broader representativeness of large study areas.The LSP accuracy of slope units increases by about 6%–10%compared with those under grid units with 30 m and 60 m resolution in the same study area's scale.The significance of environmental factors exhibits an averaging trend as study area scale increases from small to large.The importance of environmental factors varies greatly with the 60 m grid unit,but it tends to be consistent to some extent in the 30 m grid unit and the slope unit. 展开更多
关键词 Landslide susceptibility prediction Uncertainty analysis Study areas scales Mapping unit scales Slope units Random forest
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Size-dependent vibration and buckling of porous functionally graded microplates based on modified couple stress theory in thermal environments by considering a dual power-law distribution of scale effects
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作者 Feixiang TANG Shaonan SHI +2 位作者 Siyu HE Fang DONG Sheng LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第12期2075-2092,共18页
In this study,the thermodynamic behaviors of the intrinsic frequency and buckling temperature of rectangular plates of functionally graded materials(FGMs)are explored based on the modified couple stress theory(MCST)an... In this study,the thermodynamic behaviors of the intrinsic frequency and buckling temperature of rectangular plates of functionally graded materials(FGMs)are explored based on the modified couple stress theory(MCST)and the novel dual powerlaw scale distribution theory.The effects of linear,homogeneous,and non-homogeneous temperature fields on the frequency and buckling temperature of FGM microplates are evaluated in detail.The results show that the porosity greatly affects the mechanical properties of FGM plates,reducing their frequency and flexural temperature compared with non-porous plates.Different temperature profiles alter plate frequencies and buckling temperatures.The presence and pattern of scale effect parameters are also shown to be crucial for the mechanical response of FGM plates.The present research aims to provide precise guidelines for the micro-electro-mechanical system(MEMS)fabrication by elucidating the complex interplay between thermal,material,and structural factors that affect the performance of FGM plates in advanced applications. 展开更多
关键词 thermal vibration dual power law functionally graded material(FGM) pore distribution scale effect scale distribution thermal buckling
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基于多尺度Scale-Unet的单样本图像翻译
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作者 周蓬勃 冯龙 寇宇帆 《计算机技术与发展》 2024年第4期55-61,共7页
随着生成对抗网络(GAN)的发展,基于单样本的无监督图像到图像翻译(UI2I)取得了重大进展。然而,以前方法无法捕获图像中的复杂纹理并保留原始内容信息。为解决这个问题,提出了一种基于尺度可变U-Net结构(Scale—Unet)的新型单样本图像翻... 随着生成对抗网络(GAN)的发展,基于单样本的无监督图像到图像翻译(UI2I)取得了重大进展。然而,以前方法无法捕获图像中的复杂纹理并保留原始内容信息。为解决这个问题,提出了一种基于尺度可变U-Net结构(Scale—Unet)的新型单样本图像翻译结构SUGAN。所提出的SUGAN使用Scale—Unet作为生成器,利用多尺度结构和渐进方法不断改进网络结构,以从粗到细地学习图像特征。同时,提出了尺度像素损失scale-pixel来更好地约束保留原始内容信息,防止信息丢失。实验表明,与SinGAN、TuiGAN、TSIT、StyTR2等公共数据集Summer■Winter、Horse■Zebra上的方法相比,该方法生成图像的SIFID值平均降低了30%。所提方法可更好地保留图像内容信息,同时生成详细逼真的高质量图像。 展开更多
关键词 单样本图像翻译 scale-Unet 多尺度结构 渐进方法 尺度像素损失
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Scale effect removal and range migration correction for hypersonic target coherent detection
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作者 WU Shang SUN Zhi +4 位作者 JIANG Xingtao ZHANG Haonan DENG Jiangyun LI Xiaolong CUI Guolong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期14-23,共10页
The detection of hypersonic targets usually confronts range migration(RM)issue before coherent integration(CI).The traditional methods aiming at correcting RM to obtain CI mainly considers the narrow-band radar condit... The detection of hypersonic targets usually confronts range migration(RM)issue before coherent integration(CI).The traditional methods aiming at correcting RM to obtain CI mainly considers the narrow-band radar condition.However,with the increasing requirement of far-range detection,the time bandwidth product,which is corresponding to radar’s mean power,should be promoted in actual application.Thus,the echo signal generates the scale effect(SE)at large time bandwidth product situation,influencing the intra and inter pulse integration performance.To eliminate SE and correct RM,this paper proposes an effective algorithm,i.e.,scaled location rotation transform(ScLRT).The ScLRT can remove SE to obtain the matching pulse compression(PC)as well as correct RM to complete CI via the location rotation transform,being implemented by seeking the actual rotation angle.Compared to the traditional coherent detection algorithms,Sc LRT can address the SE problem to achieve better detection/estimation capabilities.At last,this paper gives several simulations to assess the viability of ScLRT. 展开更多
关键词 hypersonic target detection coherent integration(CI) scale effect(SE)removal range migration(RM)correction scaled location rotation transform(ScLRT)
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Ratification of the base of the ICS Geological Time Scale:the Global Standard Stratigraphic Age(GSSA)for the Hadean lower boundary
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作者 Jaana Halla Nora Noffke +29 位作者 Humberto Reis Stanley Awramik Andrey Bekker Alexander Brasier Flávia Callefo Adrita Choudhury Jan-Peter Duda Christopher Fedo Douglas Galante Jessica Haddock Peter Haines Linda Hinnov Axel Hofmann Martin Homann David Huston Simon Johnson Linda Kah Alan Kaufman Alex Kovalick Matheus Kuchenbecker Juha Köykkä Donald Lowe Noah Nhleko Barry Reno Evelyn Sanchez Yogmaya Shukla Albertus Smith Mark Van Zuilen Frances Westall Martin Whitehouse 《Episodes》 2024年第2期381-389,共9页
The base of the ICS(International Commission on Stratigraphy)Geological Time Scale was ratified in 2022 by defining a new Global Stratigraphic Standard Age(GSSA)for the lower boundary of the Hadean Eon(formerly 4000–... The base of the ICS(International Commission on Stratigraphy)Geological Time Scale was ratified in 2022 by defining a new Global Stratigraphic Standard Age(GSSA)for the lower boundary of the Hadean Eon(formerly 4000–3600 Ma);the age of the Solar System based on the oldest solids,calcium-aluminium inclusions(CAIs),generated in the protoplanetary disk.The formal GSSA for the Hadean base is the oldest reliable,weighted mean Ucorrected Pb–Pb age of 4567.30±0.16 Ma obtained for CAIs in primitive meteorites Allende and Efremovka.This age is supported by the 4568–4567 Ma U-corrected Pb–Pb ages of chondrules in Northwest African meteorites.The boundary sets an upper lifetime for the protoplanetary disk and timing of planet formation. 展开更多
关键词 global stratigraphic standard age gssa Hadean lower boundary RATIFICATION ICS primitive meteorites geological time scale time scale GSSA
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Scale elasticity and technical efficiency measures in two-stage network production processes:an application to the insurance sector
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作者 Alireza Amirteimoori Tofigh Allahviranloo Aliasghar Arabmaldar 《Financial Innovation》 2024年第1期2988-3008,共21页
In performance analysis with tools such as data envelopment analysis,calculations of scale properties of the frontier points are studied using both qualitative and quantitative approaches.When the production process i... In performance analysis with tools such as data envelopment analysis,calculations of scale properties of the frontier points are studied using both qualitative and quantitative approaches.When the production process is a bit complicated,the calculation needs to be modified.Most existing studies are focused on a single-stage production process under the constant or variable returns to scale specification.However,some processes have two-stage structures,and,in such processes,the concepts of scale elasticity and returns to scale are inextricably related to the conditions of the stages of production.Thus,an evaluation of efficiency,scale elasticity,and returns to scale is sensitive to stages.In this study,we introduced a procedure to calculate technical efficiency and scale elasticity in a two-stage parallel-series production system.Then,our proposed technical efficiency and scale elasticity programs are applied to real data on 20 insurance companies in Iran.After applying our estimations to a real-world insurance industry,we found that,(i)overall,the total inputs of insurers in the life insurance sector should be reduced by 9%.Moreover,the inputs of nonlife insurers should be reduced by 50%.The final output in the investment sector must be increased by 48%.(ii)There are inefficiencies among all insurers in the investment sector,and to improve technical efficiency,the income from investments should be increased significantly.(iii)Finally,the efficiency and elasticity characterizations of insurers are directly subject to stages. 展开更多
关键词 Data envelopment analysis Returns to scale scale elasticity Technical efficiency Insurance companies
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Performance of Kilometer-Scale CARAS Precipitation Product Against Ground-based Observations During 2008-2021 over Hubei,China
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作者 ZHU Chuan-dong LI Jin-xiao +5 位作者 LI Ma-jun HE Fei CHENG Chi CHEN Yu CHEN Cheng LIAO Jie 《Journal of Tropical Meteorology》 2024年第4期405-415,共11页
Based on rain gauge data during 2008-2021 from national meteorological observation stations,this study investigated the performance of the precipitation field from the 1-km-resolution version of the China Atmospheric ... Based on rain gauge data during 2008-2021 from national meteorological observation stations,this study investigated the performance of the precipitation field from the 1-km-resolution version of the China Atmospheric Realtime Analysis(CARAS)over Hubei from the perspective of climatology,multiple-time scale variations,as well as fusion accuracy and detection capability at multiple temporal scales.The results show that CARAS precipitation can reproduce the spatial distribution patterns of climatological seasonal precipitation and rainy days well over the whole of Hubei compared with observational(OBS)precipitation,albeit deviations exist between CARAS and OBS in terms of magnitude.Moreover,high correlation and consistency between CARAS and OBS can be found in multiple-time scale variations over Hubei,with correlation coefficients of interannual,seasonal,and diurnal variation generally exceeding 0.85,0.98,and 0.95,respectively.Furthermore,CARAS has a relatively higher fusion accuracy in summer and winter,and stronger/weaker detection capability in spring/winter at a daily scale.However,the detection capability of CARAS at an hourly scale is weaker than that at a daily scale.With different precipitation intensity levels considered,CARAS daily precipitation shows relatively higher fusion accuracy in estimating moderate and heavy rain,and better detection capability in capturing no rain events.The variations of accuracy metrics and detection metrics under different precipitation intensities at an hourly scale generally resemble those at a daily scale.However,CARAS precipitation at an hourly scale shows a relatively lower fusion accuracy and weaker detection capability compared with that at a daily scale.This paper provides an insight into the characteristics of systematic deviations in CARAS precipitation over Hubei,which will benefit relevant applications of CARAS in meteorological operations over Hubei and the improvement of CARAS in the future. 展开更多
关键词 China Atmospheric Realtime Analysis kilometer-scale precipitation CLIMATOLOGY multiple-time scale variations accuracy and detection capability
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Research on Developing an Assessment Scale for Tourism Experience Elements of Ancient Shu Road Heritage Trail 被引量:1
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作者 Wang Yuan Wang Bo Zhou Jiang 《Contemporary Social Sciences》 2024年第5期118-142,共25页
Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse them... Cultural ancient roads,known in Chinese as gudao,serve as heritage trails that carry historical exchanges across various regions in China.Due to their extensive preservation,wide geographical distribution,diverse thematic variations,and considerable tourist appeal,these paths have emerged as representative heritage trails,increasingly transforming into a novel tourism product experience that is highly favored by tourists and recognized by government authorities.However,research on ancient roads for tourism in China currently lacks a systematic theoretical framework,as well as relevant policies,regulations,and standards to guide their practical development.Therefore,there is a pressing need to draw upon international best practices and conduct foundational research to develop an experience element system that aligns with the perceptions,behaviors,and consumption characteristics of Chinese tourists,thereby advancing theoretical exploration in this field.This study focuses on the representative Ancient Shu Road as a case study and employs a mixed-method approach that integrates qualitative and quantitative research.It aims to construct a tourist-centric scale for the experience elements of ancient road tourism while analyzing the interactive relationship between these experience elements and tourist needs.This study addresses a significant gap in the development of indicator systems for domestic studies of ancient road tourism experiences.Ultimately,the study establishes a comprehensive scale that encompasses three core categories—trail resources and environment,facilities and services,and modes of tourism activities—along with eight primary dimensions:core resources,surrounding cultural environment,surrounding natural environment,tourism reception facilities and services,infrastructure and support services,information facilities and information services,and outdoor and recreational activities.This scale consists of thirty-two specific items,providing a robust reference for future research endeavors.Additionally,the study proposes specific development strategies related to key mechanisms,spatial configuration,and facility construction to enhance the overall development of ancient road tourism. 展开更多
关键词 ancient roads heritage trails tourism experience elements scale development
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Rate-limiting factors in hydrate decomposition through depressurization across various scales:A mini-review
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作者 Xian Sun Peng Xiao +7 位作者 Qinfeng Shi Lingban Wang Zhenbin Xu Yuhao Bu Xiaohui Wang Yifei Sun Changyu Sun Guangjin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期206-219,共14页
Natural gas hydrate is an energy resource for methane that has a carbon quantity twice more than all traditional fossil fuels combined.However,their practical application in the field has been limited due to the chall... Natural gas hydrate is an energy resource for methane that has a carbon quantity twice more than all traditional fossil fuels combined.However,their practical application in the field has been limited due to the challenges of long-term preparation,high costs and associated risks.Experimental studies,on the other hand,offer a safe and cost-effective means of exploring the mechanisms of hydrate dissociation and optimizing exploitation conditions.Gas hydrate decomposition is a complicated process along with intrinsic kinetics,mass transfer and heat transfer,which are the influencing factors for hydrate decomposition rate.The identification of the rate-limiting factor for hydrate dissociation during depressurization varies with the scale of the reservoir,making it challenging to extrapolate findings from laboratory experiments to the actual exploitation.This review aims to summarize current knowledge of investigations on hydrate decomposition on the subject of the research scale(core scale,middle scale,large scale and field tests)and to analyze determining factors for decomposition rate,considering the various research scales and their associated influencing factors. 展开更多
关键词 Gas hydrate Rate-limiting factors Research scale DEPRESSURIZATION DECOMPOSITION
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A real-time performance improvement method for composite time scale
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作者 Fangmin Wang Wenlin Li +4 位作者 Hongfei Dai Chunyi Li Jianhua Zhou Shenhui Xue Bo Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期350-357,共8页
The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern society.The improvement of CTS’s real-time performance will improve its stability,which strengths related applications’perfo... The composite time scale(CTS)provides a stable,accurate,and reliable time scale for modern society.The improvement of CTS’s real-time performance will improve its stability,which strengths related applications’performance.Aiming at this goal,a method achieved by determining the optimal calculation interval and accelerating adjustment stage is proposed in this paper.The determinants of the CTS’s calculation interval(characteristics of the clock ensemble,the measurement noise,the time and frequency synchronization system’s noise and the auxiliary output generator noise floor)are studied and the optimal calculation interval is obtained.We also investigate the effect of ensemble algorithm’s initial parameters on the CTS’s adjustment stage.A strategy to get the reasonable initial parameters of ensemble algorithm is designed.The results show that the adjustment stage can be finished rapidly or even can be shorten to zero with reasonable initial parameters.On this basis,we experimentally generate a distributed CTS with a calculation interval of 500 s and its stability outperforms those of the member clocks when the averaging time is longer than1700 s.The experimental result proves that the CTS’s real-time performance is significantly improved. 展开更多
关键词 composite time scale real-time performance calculation interval adjustment stage
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