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Independent sampling and padding for Rayleigh-Sommerfeld diffraction based on scaled convolution approach
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作者 YANG Chen FU Xi-hong +1 位作者 FU Xin-peng BAYANHESHIG 《中国光学(中英文)》 北大核心 2026年第2期367-381,共15页
We propose a novel fast numerical calculation method for the Rayleigh-Sommerfeld diffraction integral,which is developed based on the existing scaled convolution method.This approach enables fast cal-culations for gen... We propose a novel fast numerical calculation method for the Rayleigh-Sommerfeld diffraction integral,which is developed based on the existing scaled convolution method.This approach enables fast cal-culations for general cases of off-axis scenarios where the sampling intervals and numbers of the input and observation planes are unequal.Additionally,it allows for arbitrary adjustment of the sampling interval of the impulse response function,facilitating a manual trade-off between computational load and accuracy.The er-rors associated with this method,which is equivalent to interpolation,primarily arise from the discontinuities of the sampling matrix of the impulse response function on its boundaries of periodic extension.To address this issue,we propose the concept of the padding function and its construction method,and evaluate its ef-fectiveness in enhancing computational accuracy.The feasibility of the proposed method is verified by nu-merical simulation and compared with the direct integration DI-method in a simplified scenario.It shows that the proposed method has good computational accuracy for the general case where the sampling interval of the input and observation plane is not equal under non-near-field diffraction,and when the diffraction distance is large,although the computational accuracy of the proposed method cannot exceed that of the DI-method,the computational amount can be significantly reduced with almost no effect on the computational accuracy.This method provides a general numerical calculation scheme of diffraction in the non-near field case for areas such as computational holography. 展开更多
关键词 Rayleigh-Sommerfeld diffraction scaled convolution padding function
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Developing and Assessing the Reliability–Validity of the Chinese Arbitrator Competency Scale
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作者 Jiang Jindong Wei Ping 《Contemporary Social Sciences》 2026年第1期123-139,共17页
Arbitration is a key non-litigation commercial mechanism for the resolution of disputes, and the quality and credibility of its awards depend largely on the competency of the arbitrators. However, the selection and ev... Arbitration is a key non-litigation commercial mechanism for the resolution of disputes, and the quality and credibility of its awards depend largely on the competency of the arbitrators. However, the selection and evaluation systems for arbitrators in China have long faced challenges such as the vague criteria for competency and an unclear professionalization path for arbitrators. To address these issues, this study is grounded in the context of actual Chinese arbitration practice and based on the competency iceberg model. Through a methodological approach encompassing literature reviews, behavioral event interviews, expert revisions, and questionnaire surveys, a Chinese Arbitrator Competency Scale was developed and validated in this study. Examination of the findings indicated that the scale needed to consist of five dimensions—communication and coordination, cognitive skills, ethical conduct, work motivation, and personality traits—and possess a total of 28 specific indicators. Confirmatory analysis of the factors demonstrates a good fit for the five-dimensional model, with each of the dimensions exhibiting high reliability and validity. This scale is innovative in integrating the competency elements with Chinese characteristics, such as commercial acumen, crosscultural mediation skills, and adaptability to the local rule of law. This research not only enriches the competency theory in regard to the field of human resource management but also provides a scientific framework of standards and measurement tools for the selection, training, and evaluation of arbitrators. It thus has significant practical value for enhancing the professionalism and international competitiveness of China's arbitration system. 展开更多
关键词 arbitrators competency scale scale development reliability-validity assessment
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Questions and answers regarding fair use of translated scales
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《International Journal of Nursing Sciences》 2026年第1期76-76,共1页
问:如果想翻译国外作者研制的量表,需要得到其授权吗?答:翻译国外作者研制的量表,必须得到源量表作者的书面授权。问:如果在研究中计划使用中国作者翻译的量表,需要获得授权吗?答:应同时获得源量表作者和翻译量表作者的书面许可使用授... 问:如果想翻译国外作者研制的量表,需要得到其授权吗?答:翻译国外作者研制的量表,必须得到源量表作者的书面授权。问:如果在研究中计划使用中国作者翻译的量表,需要获得授权吗?答:应同时获得源量表作者和翻译量表作者的书面许可使用授权文件。 展开更多
关键词 fair use translated scales
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Efficient lactic acid production from sweet sorghum juice using Lactococcus lactis IO-1:Optimization and scale-up with low-cost nitrogen sources
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作者 Chalida Daengbussadee Lakkana Laopaiboon +4 位作者 Khanittha Fiala Thanawat Thanapornsin Ampawun Meesubmun Niphaphat Phukoetphim Pattana Laopaiboon 《Carbon Resources Conversion》 2026年第2期1-11,共11页
Among the low-cost nitrogen sources(dry spent yeast or DSY,rice bran,and soybean meal),DSY was identified as the most suitable supplement for lactic acid fermentation from sweet sorghum juice by Lactococcus lactis IO-... Among the low-cost nitrogen sources(dry spent yeast or DSY,rice bran,and soybean meal),DSY was identified as the most suitable supplement for lactic acid fermentation from sweet sorghum juice by Lactococcus lactis IO-1.However,lactic acid concentration(PL)using DSY was~22%lower than the control nitrogen source,yeast extract(YE).Statistical analysis using YE as a control nitrogen source revealed optimal conditions of 74.70 g/L of initial sugar and 15.20 g/L of YE,achieving a PL of 71.95 g/L and a 91.63%sugar consumption(SC).When DSY(22.61 g/L)containing an equivalent nitrogen content to the optimal YE was tested,PL and SC decreased to 55.13 g/L and 72.33%,respectively.Increasing DSY to 33.92 g/L(1.5 times)improved lactic acid productivity(QL)by~31%but did not enhance PL or SC.However,supplementing 33.92 g/L of DSY with 7.60 g/L of YE enhanced lactic acid production by~19-53%,achieving a PL of 70.11 g/L,SC of 92.33%,QL of 2.34 g/L⋅h,with a high lactic acid yield(YL/S),1.02 g/g.Scale-up fermentation in a 7.5-L fermenter demonstrated comparable results to those using 15.20 g/L of YE alone.These findings demonstrate that sweet sorghum juice supplemented with DSY and reduced YE is a promising medium for efficient lactic acid production,offering significant cost reduction potential for industrial applications while maintaining high productivity and yield. 展开更多
关键词 Dry spent yeast L-lactic acid Lactococcus lactis scale up Sweet sorghum
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Assessing Flourishing in a Collectivist Context:Psychometric Evaluation of the Flourishing Scale in Chinese Middle School Students
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作者 Baijun Chen Song Gui +2 位作者 Yujing Xie Lijun Ma Can Jiao 《International Journal of Mental Health Promotion》 2026年第3期72-81,共10页
Objectives:Flourishing,a central concept in positive psychology,encompasses multifaceted dimensions such as meaning,positive relationships,and engagement.Despite growing research interest,empirical studies focusing sp... Objectives:Flourishing,a central concept in positive psychology,encompasses multifaceted dimensions such as meaning,positive relationships,and engagement.Despite growing research interest,empirical studies focusing specifically on the flourishing of middle school students remain scarce.Given the critical need to promote flourishing among Chinese middle school students,the study aimed to adapt Diener’s Flourishing Scale for Chinese middle school students,examine its psychometric properties,and establish its measurement invariance across gender and time within this population.Methods:Participants were recruited from secondary schools in two Chinese provinces.The Chinese versions of the Flourishing Scale(CFS),along with the Index of Well-being(IWB)and the Satisfaction with Life Scale(SWLS),were employed.Data collection occurred in three phases,the first two for exploratory factor analysis(EFA)and confirmatory factor analysis(CFA),respectively,and the last one for testing longitudinal measurement invariance and gender measurement invariance.Results:The CFS demonstrated excellent discrimination and consistency with Diener’s original model.Significant positive correlations emerged between the CFS scores and well-being(r=0.75,p<0.01)as well as life satisfaction(r=0.74,p<0.01).Cronbach’sαwas 0.948,and the Pearson correlation coefficient(PCC)for test-retest reliability was 0.85(p<0.01).The CFS demonstrated strict measurement invariance across both gender and time.Conclusion:The CFS demonstrates robust psychometric properties—including structural validity,reliability,and measurement invariance—for its application among Chinese middle school students. 展开更多
关键词 Flourishing scale Chinese middle school students psychometric properties positive psychology
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Decoding China’s urban transformation:Multiscale analysis of urban spatial structures and their influencing factors(2007-2023)
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作者 Yan Wang Kai Liu 《Chinese Journal of Population,Resources and Environment》 2026年第1期54-66,共13页
Investigating urban spatial structures(USSs)and their influencing factors at different spatial scales is crucial for promoting sustainable urban transformation.Based on nighttime light datasets and the Herfindahl-Hirs... Investigating urban spatial structures(USSs)and their influencing factors at different spatial scales is crucial for promoting sustainable urban transformation.Based on nighttime light datasets and the Herfindahl-Hirschman index(HHI),this study analyzes USS characteristics in China from 2007 to 2023 on two spatial scales-prefecture-level cities and urban agglomerations.It also explores structural influencing factors,including the economy,infrastructure,society,and government intervention.We find that:(1)HHI values for both cities and urban agglomerations exhibit a decreasing trend,indicating a USS for both that is evolving toward polycentricity;(2)economic development promotes a polycentric structure at both spatial scales,whereas government intervention drives a monocentric structure;and(3)postal and communication infrastructure have conflicting effects on USSs,encouraging a monocentric structure at the city scale but fostering polycentricity at the urban agglomeration scale. 展开更多
关键词 Urban spatial structure Nighttime light datasets Herfindahl-Hirschman index Different spatial scales
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A Scale Separation Hybrid Predictive Model and Its Application to Predict Summer Monthly Precipitation in Northeast China
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作者 Lei YU Aihui WANG Changzheng LIU 《Advances in Atmospheric Sciences》 2026年第3期504-528,共25页
Northeast China serves as an important crop production region.Accurately forecasting summer precipitation in Northeast China(NEC-PR)has been a challenge due to its wide range of time scales influenced by varying clima... Northeast China serves as an important crop production region.Accurately forecasting summer precipitation in Northeast China(NEC-PR)has been a challenge due to its wide range of time scales influenced by varying climatic conditions.This study presents a scale separation hybrid statistical model with recurrent neural network(SS-RNN)to predict the summer monthly NEC-PR.The SS-RNN model decomposes the multiple scales of the NEC-PR into several spatiotemporal intrinsic mode functions covering annual to decadal time scales.This strategy provides a way to derive appropriate predictors and establish predictive models for the primary spatial modes of the NEC-PR at various time scales.Our results demonstrate substantial improvements by the SS-RNN model in predicting the summer monthly NEC-PR as compared with dynamic models,particularly in predicting the spatial pattern of the NEC-PR.In this paper we take August,the month of the highest NEC-PR,to assess our model skill.Independent forecasts of the August NEC-PR over the period 2021–24 achieve significant spatial anomaly correlation coefficients,reaching a maximum value of 0.83.Additional verifications by station observations show that the model hits most station anomalies,achieving a mean predictive skill score of 90. 展开更多
关键词 Northeast China precipitation scale separation approach statistical predictive model recurrent neural network predictive model
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Multi-Timescale Coordinated Optimal Dispatch of Active Distribution Networks Incorporating Thermal Storage Electric Heating Clusters
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作者 Song Zhang Yang Yu +1 位作者 Shuguang Li Xue Li 《Energy Engineering》 2026年第3期459-480,共22页
Thermal storage electric heating(TSEH),as a prevalent variable load resource,offers significant potential for enhancing system flexibility when aggregated into a cluster.To address the uncertainties of renewable energ... Thermal storage electric heating(TSEH),as a prevalent variable load resource,offers significant potential for enhancing system flexibility when aggregated into a cluster.To address the uncertainties of renewable energy and load forecasting in active distribution networks(ADN),this paper proposes a multi-timescale coordinated optimal dispatch strategy that incorporates TSEH clusters.It utilizes the thermal storage characteristics and short-term regulation capabilities of TSEH,along with the rapid and gradual response characteristics of resources in active distribution grids,to develop a coordinated optimization dispatch mechanism for day-ahead,intraday,and real-time stages.It provides a coordinated optimized dispatch technique across several timescales for active distribution grids,taking into account the integration of TSEH clusters.The proposed method is validated on a modified IEEE 33-node system.Simulation results demonstrate that the participation of TSEH in collaborative optimization significantly reduces the total system operating cost by 8.71%compared to the scenario without TSEH.This cost reduction is attributed to a 10.84%decrease in interaction costs with the main grid and a 47.41%reduction in network loss costs,validating effective peak shaving and valley filling.The multi-timescale framework further enhances economic efficiency,with overall operating costs progressively decreasing by 3.91%(intraday)and 4.59%(real-time),and interaction costs further reduced by 5.34%and 9.25%,respectively.Moreover,the approach enhances system stability by effectively suppressing node voltage fluctuations and ensuring all voltages remain within safe operating limits during real-time operation.Therefore,the proposed approach achieves rational coordination of diverse resources,significantly improving the economic efficiency and stability of ADNs. 展开更多
关键词 Active distribution network thermal storage electric heating distributed energy resources rolling optimization multiple time scales
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The Interaction Mechanism Between Urban Scale Hierarchy and Urban Networks in China:An Analysis Based on A Spatial Simultaneous Equation Model
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作者 ZHOU Ying ZHENG Wensheng WANG Xiaofang 《Chinese Geographical Science》 2026年第1期19-33,共15页
Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefor... Owing to intensified globalization and informatization,the structures of the urban scale hierarchy and urban networks between cities have become increasingly intertwined,resulting in different spatial effects.Therefore,this paper analyzes the spatial interaction between urban scale hierarchy and urban networks in China from 2019 to 2023,drawing on Baidu migration data and employing a spatial simultaneous equation model.The results reveal a significant positive spatial correlation between cities with higher hierarchy and those with greater network centrality.Within a static framework,we identify a positive interaction between urban scale hierarchy and urban network centrality,while their spatial cross-effects manifest as negative neighborhood interactions based on geographical distance and positive cross-scale interactions shaped by network connections.Within a dynamic framework,changes in urban scale hierarchy and urban networks are mutually reinforcing,thereby widening disparities within the urban hierarchy.Furthermore,an increase in a city’s network centrality had a dampening effect on the population growth of neighboring cities and network-connected cities.This study enhances understanding of the spatial organisation of urban systems and offers insights for coordinated regional development. 展开更多
关键词 urban scale hierarchy urban networks spatial interaction spatial spillover effect Baidu migration data spatial simultaneous equation model China
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Uniform wafer-scale MOCVD homoepitaxy of β-Ga_(2)O_(3)on 2-inch(010)substrates
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作者 Xuanze Zhou Haozhong Wu +7 位作者 Yuanjie Ding Ziyuan Wang Zhiyu Zhou Ning Xia Song Zhang Guangwei Xu Hui Zhang Shibing Long 《Chinese Physics B》 2026年第1期576-580,共5页
The(010)orientation ofβ-Ga_(2)O_(3)is a highly promising platform for next-generation lateral power electronics due to its superior theoretical transport properties.However,progress has been impeded by the unavailabi... The(010)orientation ofβ-Ga_(2)O_(3)is a highly promising platform for next-generation lateral power electronics due to its superior theoretical transport properties.However,progress has been impeded by the unavailability of large-area substrates,limiting studies to small-scale samples.Leveraging the recent emergence of 2-inch wafers,we report the first demonstration of homoepitaxial growth on a 2-inch,Fe-doped semi-insulating(010)β-Ga_(2)O_(3)substrate by metal-organic chemical vapor deposition(MOCVD).A systematic,wafer-scale characterization reveals the successful growth of a highquality epitaxial film.High-resolution x-ray diffraction shows an excellent crystalline structure,with a rocking curve full-width ranging from 21.0 arcsec to 103.0 arcsec.Atomic force microscopy confirms an atomically smooth surface with a root-mean-square roughness below 1.53 nm,displaying a distinct step-flow growth mode across the wafer.Furthermore,mercury-probe capacitance-voltage mapping indicates a well-controlled carrier concentration of~2×10~(18)cm~(-3)with a RSD of 5.12%.This work provides the first comprehensive assessment of 2-inch(010)Ga_(2)O_(3)epitaxial wafers,validating a critical material platform for the development and future manufacturing of high-performance power devices. 展开更多
关键词 β-Ga_(2)O_(3) metal-organic chemical vapor deposition(MOCVD) wafer scale UNIFORMITY
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Complex τ Electric Dipole Moment from GeV-Scale New Physics
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作者 Zhong-Lv Huang Xin-Yu Du +2 位作者 Xiao-Gang He Chia-Wei Liu Zi-Yue Zou 《Chinese Physics Letters》 2026年第3期28-33,共6页
Among the charged leptons,theτelectric dipole moment dτis the least constrained.We show that the Im[d_(τ)]imposes strong constraints on new physics that have yet to be discussed.Motivated in particular by the Super... Among the charged leptons,theτelectric dipole moment dτis the least constrained.We show that the Im[d_(τ)]imposes strong constraints on new physics that have yet to be discussed.Motivated in particular by the Super Tau-Charm Facility(STCF),which will provide a uniquely clean environment for precisionτ-physics,we study the momentum-transfer dependence of d_(τ)(q^(2))and compare the projected sensitivities of STCF and BelleⅡ.Our analysis shows that an axion-like coupling of the τ lepton can induce sizable real and imaginary components of the EDM.The predicted EDM values may approach the present experimental sensitivities,making them accessible to future measurements at Belle II and the STCF. 展开更多
关键词 momentum transfer dependence axion coupling new physics experimental sensitivities super tau charm facility LEPTON charged leptonsthe electric dipole moment gev scale new physics
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基于混合t-t Location-scale分布的风电功率波动特性研究
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作者 徐凯 熊国江 《电气工程学报》 北大核心 2026年第1期412-422,共11页
风电功率波动的随机性和不确定性是限制风能消纳的主要原因之一,风电功率的波动会影响风电功率的准确预测。定量描述风电功率的波动特性成为解决这些问题的关键。从风电功率波动“尖峰厚尾”的特征出发,将t分布与t Location-scale分布... 风电功率波动的随机性和不确定性是限制风能消纳的主要原因之一,风电功率的波动会影响风电功率的准确预测。定量描述风电功率的波动特性成为解决这些问题的关键。从风电功率波动“尖峰厚尾”的特征出发,将t分布与t Location-scale分布两者的优势结合,提出混合t-t Location-scale分布。为了避免以往方法参数估计精度不足的问题,引入一种智能优化算法——正余弦优化算法,来进行分布模型的参数估计。将所提模型与正态分布、混合t Location-scale分布等5种模型进行对比,并从15 min、30 min和45 min 3个滑动平均时段长度验证了模型的适用性。通过我国西北地区3个风电场的历史数据进行仿真试验,对比3个评价指标,发现所提模型对风电功率波动具有很好的拟合性能。 展开更多
关键词 混合t-t Location-scale分布 风电功率波动 正余弦优化算法 滑动平均法 时间尺度
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SIMULATION OF THE INTERFACED STRUCTURAL COMPONENT BASED ON A MULTIPLE-TIME-SCALE ALGORITHM
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作者 Keke Tang Xianqiao Wang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2014年第4期353-363,共11页
A multiple-time-scale algorithm is developed to numerically simulate certain structural components in civil structures where local defects inevitably exist. Spatially, the size of local defects is relatively small com... A multiple-time-scale algorithm is developed to numerically simulate certain structural components in civil structures where local defects inevitably exist. Spatially, the size of local defects is relatively small compared to the structural scale. Different length scales should be adopted considering the efficiency and computational cost. In the principle of physics, different length scales are stipulated to correspond to different time scales. This concept lays the foundation of the framework for this multiple-time-scale algorithm. A multiple-time-scale algorithm, which involves different time steps for different regions, while enforcing the compatibility of displacement, force and stress fields across the interface, is proposed. Furthermore, a defected beam component is studied as a numerical sample. The structural component is divided into two regions: a coarse one and a fine one; a micro-defect exists in the fine region and the finite element sizes of the two regions are diametrically different. Correspondingly, two different time steps are adopted. With dynamic load applied to the beam, stress and displacement distribution of the defected beam is investigated from the global and local perspectives. The numerical sample reflects that the proposed algorithm is physically rational and computationally efficient in the potential damage simulation of civil structures. 展开更多
关键词 multiple-time-scale algorithm defected beam interface structural component civil structures
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ScaleMamba-YOLO:基于MambaYOLO的多尺度医学目标检测模型
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作者 覃晓 钱泉梅 《南宁师范大学学报(自然科学版)》 2026年第2期63-75,共13页
针对MambaYOLO在医学影像分析中存在的多尺度适应性不足(病灶尺寸差异大导致固定感受野效果受限)和背景干扰敏感(正常组织噪声影响检测)2个关键问题,本研究提出了一种基于MambaYOLO的多尺度医学目标检测模型ScaleMamba-YOLO。首先,针对... 针对MambaYOLO在医学影像分析中存在的多尺度适应性不足(病灶尺寸差异大导致固定感受野效果受限)和背景干扰敏感(正常组织噪声影响检测)2个关键问题,本研究提出了一种基于MambaYOLO的多尺度医学目标检测模型ScaleMamba-YOLO。首先,针对尺度特征捕捉不足的问题,设计了医学多尺度局部特征增强模块(Medical Multi-scale Local Feature Enhancement Block),通过异构卷积核并行架构实现病理特征的全尺度覆盖,实现了对微小病灶和弥散性大病灶的协同检测。其次,为了减少背景噪声放大,提出特征聚合提取模块(Partial-enhanced C2F),采用部分卷积技术选择性保留关键特征通道,有效抑制了医学影像中正常组织区域的背景干扰。最后,为了验证模型的有效性,在Br35H(脑部MRI肿瘤)和PLoPy(结肠镜息肉)两个典型的公开医学数据集上进行了测试。实验结果表明,ScaleMamba-YOLO模型的平均精度均值(AP)分别达到72.7%和85.7%,相较于基线MambaYOLO模型,AP分别提升了2.2个百分点和1.7个百分点。这表明ScaleMamba-YOLO模型能有效克服多尺度适应性不足和背景干扰问题,可以显著提升模型对不同尺寸医学病灶的检测精度。 展开更多
关键词 Mamba MambaYOLO 多尺度特征融合 局部特征增强 医学影像分析
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智算中心Scale-Out网络的演进及GSE的实践 被引量:1
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作者 程伟强 李新双 +1 位作者 白艳 吕勇 《中兴通讯技术》 北大核心 2025年第2期14-20,共7页
探讨了人工智能(AI)大模型时代智算中心网络面临的技术挑战,重点分析了传统互联网协议(IP)网络在负载均衡和突发流量处理方面的局限性,并对比了基于以太网融合远程直接内存访问(RoCE)的优化与网络架构重构两种技术路线。研究聚焦中国自... 探讨了人工智能(AI)大模型时代智算中心网络面临的技术挑战,重点分析了传统互联网协议(IP)网络在负载均衡和突发流量处理方面的局限性,并对比了基于以太网融合远程直接内存访问(RoCE)的优化与网络架构重构两种技术路线。研究聚焦中国自主研发的全调度以太网(GSE)技术,详细阐述了其核心技术:基于报文容器(PKTC)的负载均衡机制和动态全调度队列(DGSQ)端到端拥塞控制技术。这些技术有效解决了智算网络中的流量极化和拥塞丢包问题。同时,系统分析了GSE网络设备在接口设计、转发引擎和队列管理等关键环节的创新架构,论证了GSE技术在构建高带宽、低时延、无阻塞新型网络方面的技术优势,为智算中心网络演进提供了重要参考。 展开更多
关键词 AI大模型 智算中心 scale-Out GSE RoCE 负载均衡 拥塞避免
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嵌入自适应空间注意力的Scaled-YOLOv4小目标检测模型 被引量:2
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作者 张家源 窦全胜 唐焕玲 《计算机应用与软件》 北大核心 2025年第6期218-224,240,共8页
针对目标检测方法中网络采用固定感受野使卷积提取特征时只关注常规尺寸目标而忽略小目标的特征造成检测精度低的问题,提出自适应空间注意力机制,增加并行的不同大小卷积核,嵌入Scaled-YOLOv4残差结构的3×3卷积层中,使网络根据不... 针对目标检测方法中网络采用固定感受野使卷积提取特征时只关注常规尺寸目标而忽略小目标的特征造成检测精度低的问题,提出自适应空间注意力机制,增加并行的不同大小卷积核,嵌入Scaled-YOLOv4残差结构的3×3卷积层中,使网络根据不同的尺寸的物体自主调节感受野大小加强对小目标特征的提取。实验结果表明,新的网络模型能有效提升小目标的检测精度,并改善原模型存在的误检和漏检问题。在MSCOCO和PASCAL VOC等数据集上的检测精度均比之前有较大提升。 展开更多
关键词 小目标检测 scaled-YOLOv4 深度学习 注意力机制 自适应感受野
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Revisiting scale effect on joint roughness coefficient and shear strength considering sampling methods and geometric characteristics 被引量:1
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作者 Qing Lü Xueheng Cai +2 位作者 Luxiang Wu Jun Zheng Bo Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第5期2843-2856,共14页
The scale effect on shear strength of rock joints is well-documented.However,whether scale effects are negative,positive,or even exist or not is still controversial.Joint roughness significantly influences the shear s... The scale effect on shear strength of rock joints is well-documented.However,whether scale effects are negative,positive,or even exist or not is still controversial.Joint roughness significantly influences the shear strength of rock joints.Compared to the shear tests,using the joint roughness coefficient(JRC)and its roughness parameters offers a more convenient method for describing the scale effect on shear strength.However,it is crucial to understand that the scale effect mechanisms of JRC are distinct from those of shear strength.Therefore,this paper aims to clarify these distinct mechanisms.By digitally extracting roughness parameters from granite samples,it is found that the scale effect of roughness parameters mainly comes from the sampling methods and the geometric characteristics of parameters.Furthermore,a full data sampling method considering heterogeneity is proposed to obtain more representative roughness parameters.To reveal the scale effect mechanisms of shear strength,Gaussian filtering is firstly used to separate the waviness and unevenness components of roughness,facilitating a deeper understanding of the geometric characteristics of roughness.It is suggested that the wavelength of the waviness component can reflect the scale effect on shear strength.Secondly,numerical simulations of ideal artificial joint models are conducted to validate that the wavelength of the waviness component serves as the dividing point between positive and negative scale effects.The mechanical mechanisms of positive and negative scale effects are also interpreted.Finally,these mechanisms successfully elucidate the occurrence patterns of the scale effect on natural joint profiles. 展开更多
关键词 Rock joint Joint roughness coefficient(JRC) Shear strength scale effect
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On Mason Reset Based control and the scale of integration
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作者 Yu Hu Zhiqiang Gao 《Control Theory and Technology》 2025年第3期479-493,共15页
Mason Reset(MR),a groundbreaking invention by Clesson E.Mason in 1930 that later became a part of“the universal approach to process control instrumentation”,is revisited in this paper and is shown to consists of thr... Mason Reset(MR),a groundbreaking invention by Clesson E.Mason in 1930 that later became a part of“the universal approach to process control instrumentation”,is revisited in this paper and is shown to consists of three actions:fast(errorcorrection),medium(negative feedback for expanded proportional band)and slow(reset for zero steady-state error).The focus of the paper is on the reset action,generated from a positive feedback loop,and its underlying principles with profound implications to our understanding and practice of automatic control,both basic and advanced.For example,we note that reset control and integral control,contrary to common belief,differ fundamentally in design principle and in practicality.Such difference comes to a head in the event of integrator windup:while reset windup is a problem of actuator saturation,the integrator windup is a runaway situation due to controller instability.In fact,there is no advantage gained in replacing MR with an integrator.In other words,one should not integrate the error directly as in standard PID,since doing so makes the closed-loop system internally unstable.With MR-based control formulated in this paper,there is no such threat of instability and,therefore,no need for any anti-windup mechanisms.Furthermore,the integral control is made scalable in this framework as a tradeoff between the steady-state accuracy and the controller stability.This leads to a novel MR-based control design,scalable in gain and in time to accommodate various process characteristics and design specifications.Simple in construction and transparent in principle,this MR-based control,as a basic framework of design,is readily deployable in scale. 展开更多
关键词 Mason Reset scale of integration Gain scale Time scale Reset windup Integrator windup Mason Reset Based control
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Multi-scale feature fusion optical remote sensing target detection method 被引量:1
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作者 BAI Liang DING Xuewen +1 位作者 LIU Ying CHANG Limei 《Optoelectronics Letters》 2025年第4期226-233,共8页
An improved model based on you only look once version 8(YOLOv8)is proposed to solve the problem of low detection accuracy due to the diversity of object sizes in optical remote sensing images.Firstly,the feature pyram... An improved model based on you only look once version 8(YOLOv8)is proposed to solve the problem of low detection accuracy due to the diversity of object sizes in optical remote sensing images.Firstly,the feature pyramid network(FPN)structure of the original YOLOv8 mode is replaced by the generalized-FPN(GFPN)structure in GiraffeDet to realize the"cross-layer"and"cross-scale"adaptive feature fusion,to enrich the semantic information and spatial information on the feature map to improve the target detection ability of the model.Secondly,a pyramid-pool module of multi atrous spatial pyramid pooling(MASPP)is designed by using the idea of atrous convolution and feature pyramid structure to extract multi-scale features,so as to improve the processing ability of the model for multi-scale objects.The experimental results show that the detection accuracy of the improved YOLOv8 model on DIOR dataset is 92%and mean average precision(mAP)is 87.9%,respectively 3.5%and 1.7%higher than those of the original model.It is proved the detection and classification ability of the proposed model on multi-dimensional optical remote sensing target has been improved. 展开更多
关键词 multi scale feature fusion optical remote sensing feature map improve target detection ability optical remote sensing imagesfirstlythe target detection feature fusionto enrich semantic information spatial information
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Quantitative scale validation of the Dimensional Anhedonia Rating Scale in the treatment of Chinese patients with major depressive disorder
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作者 Xiaojing Gu Yun-Ai Su +6 位作者 Jingyu Lin Xiaowei Chen Donald M Bushnell Dongjing Fu Carol Jamieson Heather Rozjabek Tianmei Si 《General Psychiatry》 2025年第2期144-152,共9页
Background The patient-reported Dimensional Anhedonia Rating Scale(DARS)has been adapted into Chinese,so there is a need to evaluate its measurement properties in a Chinese population.Aims To evaluate the reliability ... Background The patient-reported Dimensional Anhedonia Rating Scale(DARS)has been adapted into Chinese,so there is a need to evaluate its measurement properties in a Chinese population.Aims To evaluate the reliability and validity of the DARS among Chinese individuals with major depressive disorder(MDD)and its treatment sensitivity in a prospective clinical study.Methods Data were from a multicentre,prospective clinical study(NCT03294525),which recruited both patients with MDD,who were followed for 8 weeks,and healthy controls(HCs),assessed at baseline only.The analysis included confirmatory factor analysis,validity and sensitivity to change.Results Patients’mean(standard deviation(SD))age was 34.8(11.0)years,with 68.7%being female.75.2%of patients with MDD had melancholic features,followed by 63.8%with anxious distress.Patients had experienced MDD for a mean(SD)of 9.2(18)months.DARS scores covered the full range of severity with no major floor or ceiling effects.Confirmatory factor analysis showed adequate fit statistics(comparative fit index 0.976,goodness-of-fit index 0.935 and root mean square error of approximation 0.055).Convergent validity with anhedonia-related measures was confirmed.While the correlation between the DARS and the Hamilton Depression Rating Scale was not strong(r=0.31,baseline),the DARS was found to differentiate between levels of depression.Greater improvements in DARS scores were seen with the Hamilton Rating Scale for Depression responder group(effect size 1.16)compared with the non-responder group(effect size 0.46).Conclusions This study comprehensively evaluated the measurement properties of the DARS using a Chinese population with MDD.Overall,the Chinese version of DARS demonstrates good psychometric properties and has been found to be responsive to change during antidepressant treatment.The DARS is a suitable scale for assessing patient-reported anhedonia in future clinical trials. 展开更多
关键词 RELIABILITY Validity major depressive disorder mdd Quantitative scale validation Chinese population Major Depressive Disorder Dimensional Anhedonia Rating scale dimensional anhedonia rating scale dars
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