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Convolutional Graph Neural Network with Novel Loss Strategies for Daily Temperature and Precipitation Statistical Downscaling over South China
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作者 Wenjie YAN Shengjun LIU +6 位作者 Yulin ZOU Xinru LIU Diyao WEN Yamin HU Dangfu YANG Jiehong XIE liang zhao 《Advances in Atmospheric Sciences》 2025年第1期232-247,共16页
Traditional meteorological downscaling methods face limitations due to the complex distribution of meteorological variables,which can lead to unstable forecasting results,especially in extreme scenarios.To overcome th... Traditional meteorological downscaling methods face limitations due to the complex distribution of meteorological variables,which can lead to unstable forecasting results,especially in extreme scenarios.To overcome this issue,we propose a convolutional graph neural network(CGNN)model,which we enhance with multilayer feature fusion and a squeeze-and-excitation block.Additionally,we introduce a spatially balanced mean squared error(SBMSE)loss function to address the imbalanced distribution and spatial variability of meteorological variables.The CGNN is capable of extracting essential spatial features and aggregating them from a global perspective,thereby improving the accuracy of prediction and enhancing the model's generalization ability.Based on the experimental results,CGNN has certain advantages in terms of bias distribution,exhibiting a smaller variance.When it comes to precipitation,both UNet and AE also demonstrate relatively small biases.As for temperature,AE and CNNdense perform outstandingly during the winter.The time correlation coefficients show an improvement of at least 10%at daily and monthly scales for both temperature and precipitation.Furthermore,the SBMSE loss function displays an advantage over existing loss functions in predicting the98th percentile and identifying areas where extreme events occur.However,the SBMSE tends to overestimate the distribution of extreme precipitation,which may be due to the theoretical assumptions about the posterior distribution of data that partially limit the effectiveness of the loss function.In future work,we will further optimize the SBMSE to improve prediction accuracy. 展开更多
关键词 statistical downscaling convolutional graph neural network feature processing SBMSE loss function
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河北承德地区土壤硒元素地球化学特征、地质成因及其生态环境评价
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作者 魏浩 卫晓锋 +7 位作者 王京彬 朱苏加 杨帆 梁钊 田晓霞 李炜 贾文茹 于开宁 《中国地质》 CAS CSCD 北大核心 2024年第4期1290-1303,共14页
【研究目的】查明承德地区土壤硒的分布特征及地质成因,为当地土壤硒的勘查及有效利用提供科学依据。【研究方法】通过地质调查查明该区成土母质类型,利用X-射线荧光光谱法、电感耦合等离子体发射光谱法、凯氏定氮法等获取了553个土壤... 【研究目的】查明承德地区土壤硒的分布特征及地质成因,为当地土壤硒的勘查及有效利用提供科学依据。【研究方法】通过地质调查查明该区成土母质类型,利用X-射线荧光光谱法、电感耦合等离子体发射光谱法、凯氏定氮法等获取了553个土壤样品及66件岩矿石样品中硒及多个元素的含量,并利用SPSS软件分析数据,结合地质作用分析地质成因。【研究结果】研究区成土母质大致分为9类,表层土壤中硒含量最小值为0.016mg/kg,最大值为0.743 mg/kg,平均值为0.17 mg/kg,土壤平均硒含量仅为全国土壤平均硒含量的1/2,处于缺乏等级。铁矿石、金矿石、铅锌矿石中硒含量均值分别为0.860 mg/kg、1.233 mg/kg、3.365 mg/kg,明显高于各类矿石的尾矿及围岩。【结论】承德地区土壤硒整体含量很低,主要决定于成土母质,分布特征受控于地质建造。富硒土壤区域集中在隆化县南部(A区)、承德市南部(B区)(双滦区、双桥区)、宽城县东部(C区)。C区属于“岩石风化型”,与含硒量高的原生碳酸盐岩+碳质泥岩地层组合有关;B区属于“成矿伴生型”,与铅锌矿成矿过程中硒与金属硫化物的伴生关系及硒与硫的替代关系有关;A区属于“河道沉积型”,与河道沉积过程中河湖冲动力驱动、有机质的吸附作用有关。承德南部富硒区域具有发展林果经济的天然优势,围场县处于低硒环境,是引发克山病等地方病流行的因素之一。 展开更多
关键词 土壤硒 分布特征 相关性分析 地质成因 农业地质调查工程 承德市 河北省
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柔性屏COF弯折结构的正交试验优化设计 被引量:1
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作者 郑宏兵 胥奇 +1 位作者 梁钊 柳登明 《液晶与显示》 CAS CSCD 北大核心 2024年第9期1205-1213,共9页
OLED(Organic Light-Emitting Diode)屏幕COF(Chip on Film)连接过渡区的金属层在模组弯折阶段和可靠性验证阶段容易发生断裂,导致屏幕显示异常。本文采用试验设计(Design of Experiment,DOE)方法,以弯折成型状态和可靠性状态下的金属... OLED(Organic Light-Emitting Diode)屏幕COF(Chip on Film)连接过渡区的金属层在模组弯折阶段和可靠性验证阶段容易发生断裂,导致屏幕显示异常。本文采用试验设计(Design of Experiment,DOE)方法,以弯折成型状态和可靠性状态下的金属层应力最小作为试验指标,以泡棉厚度、泡棉偏移、金属包覆层(Metal Cover Layer,MCL)厚度和U型膜偏移作为影响因子,设计L9(34)正交试验方案,使用有限元方法对9组试验方案进行数值模拟和分析,并进行弯折成型和可靠性状态下的试验验证,最终获得了最优组合方案。有限元方法和试验结果表明,U型膜贴附偏移量对COF区的金属层弯折应力的影响最大,其次是泡棉厚度,再次是MCL厚度和泡棉贴附偏移量。最优组合方案在弯折成型和可靠性状态下皆具有最小的金属层应力,其值分别为57 MPa和523 MPa。最优组合方案的弯折成型和可靠性试验达到了100%的产品良品率,满足设计和生产要求。 展开更多
关键词 金属层 断裂 正交试验设计 弯折 可靠性 良品率
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华北东部晚古生代过渡相煤系地层低阻成因、控制因素与地质意义
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作者 侯中帅 梁钊 陈世悦 《煤炭科学技术》 EI CAS CSCD 北大核心 2024年第3期159-168,共10页
华北东部晚古生代过渡相煤系地层中低阻层发育,明确其成因类型、控制因素以及地质意义,可以充分揭示其中所包含的地质信息,对于相关层系油气资源评价和勘探部署具有积极意义。本文以华北东部太原组和山西组中低阻层为研究对象,综合运用... 华北东部晚古生代过渡相煤系地层中低阻层发育,明确其成因类型、控制因素以及地质意义,可以充分揭示其中所包含的地质信息,对于相关层系油气资源评价和勘探部署具有积极意义。本文以华北东部太原组和山西组中低阻层为研究对象,综合运用岩心、薄片、扫描电镜、碳氧同位素和测录井资料,围绕其成因类型、控制因素和地质意义开展研究。结果表明:华北东部晚古生代过渡相煤系低阻层主要发育在太1段和山2段,成因类型包括砂泥岩薄互层、高束缚水体积和发育导电矿物,沉积作用和成岩作用控制了低阻的形成;太1段低阻的成因为砂泥岩薄互层和高束缚水体积,潮汐作用导致的潮汐成因层理和微细孔隙发育促进了障壁海岸背景下太1段低阻的形成,山2段低阻的成因为菱铁矿的密集发育,稳定的覆水还原环境和沉积有机物的成岩演化共同控制了三角洲背景下山2段低阻的形成;太1段的低阻和高毛细管束缚水体积指示着潮坪沉积,说明太原组自下而上为一个海退的过程,是对早二叠世早期冈瓦纳冰川迅速扩张和全球海平面快速下降的响应,山2段的低阻和高光电吸收截面指数指示着三角洲前缘沉积,说明山西组由一期三角洲沉积组成。 展开更多
关键词 砂泥岩薄互层 高束缚水体积 导电矿物 低阻 煤系地层
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Evolution and Prospects of Foundation Models: From Large Language Models to Large Multimodal Models 被引量:1
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作者 Zheyi Chen Liuchang Xu +5 位作者 Hongting Zheng Luyao Chen Amr Tolba liang zhao Keping Yu Hailin Feng 《Computers, Materials & Continua》 SCIE EI 2024年第8期1753-1808,共56页
Since the 1950s,when the Turing Test was introduced,there has been notable progress in machine language intelligence.Language modeling,crucial for AI development,has evolved from statistical to neural models over the ... Since the 1950s,when the Turing Test was introduced,there has been notable progress in machine language intelligence.Language modeling,crucial for AI development,has evolved from statistical to neural models over the last two decades.Recently,transformer-based Pre-trained Language Models(PLM)have excelled in Natural Language Processing(NLP)tasks by leveraging large-scale training corpora.Increasing the scale of these models enhances performance significantly,introducing abilities like context learning that smaller models lack.The advancement in Large Language Models,exemplified by the development of ChatGPT,has made significant impacts both academically and industrially,capturing widespread societal interest.This survey provides an overview of the development and prospects from Large Language Models(LLM)to Large Multimodal Models(LMM).It first discusses the contributions and technological advancements of LLMs in the field of natural language processing,especially in text generation and language understanding.Then,it turns to the discussion of LMMs,which integrates various data modalities such as text,images,and sound,demonstrating advanced capabilities in understanding and generating cross-modal content,paving new pathways for the adaptability and flexibility of AI systems.Finally,the survey highlights the prospects of LMMs in terms of technological development and application potential,while also pointing out challenges in data integration,cross-modal understanding accuracy,providing a comprehensive perspective on the latest developments in this field. 展开更多
关键词 Artificial intelligence large language models large multimodal models foundation models
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Effect of different cold air intensities and their lagged effects on outpatient visits for respiratory illnesses in Handan in different seasons 被引量:1
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作者 Xingshan Zhang Guiqin Fu +4 位作者 liang zhao Ji Wang Caimeng liang Juanhuai Wang Meng Li 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期39-44,共6页
本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分... 本文利用2016年到2019年邯郸市气象要素和呼吸系统疾病门诊数据,分析了不同季节不同强度的冷空气过程及其对呼吸系统疾病的影响,结果显示:尽管呼吸系统疾病在冬季高发,夏季最低,但冷空气对呼吸系统疾病的影响在夏,春季最大,就诊人数分别在冷空气日后两天和五天增加18.4%和13.3%,而冬季就诊人数在冷空气日后三天仅增加3.2%.冷空气对疾病影响的滞后时间在夏,秋和冬季随冷空气强度的增加而减少,而春季的滞后时间总是很长.这些发现可为科学应对气候异常导致的人群健康风险提供针对性依据. 展开更多
关键词 冷空气过程 降温幅度 呼吸系统疾病 滞后效应
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Data-driven Wasserstein distributionally robust chance-constrained optimization for crude oil scheduling under uncertainty
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作者 Xin Dai liang zhao +4 位作者 Renchu He Wenli Du Weimin Zhong Zhi Li Feng Qian 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期152-166,共15页
Crude oil scheduling optimization is an effective method to enhance the economic benefits of oil refining.But uncertainties,including uncertain demands of crude distillation units(CDUs),might make the production plans... Crude oil scheduling optimization is an effective method to enhance the economic benefits of oil refining.But uncertainties,including uncertain demands of crude distillation units(CDUs),might make the production plans made by the traditional deterministic optimization models infeasible.A data-driven Wasserstein distributionally robust chance-constrained(WDRCC)optimization approach is proposed in this paper to deal with demand uncertainty in crude oil scheduling.First,a new deterministic crude oil scheduling optimization model is developed as the basis of this approach.The Wasserstein distance is then used to build ambiguity sets from historical data to describe the possible realizations of probability distributions of uncertain demands.A cross-validation method is advanced to choose suitable radii for these ambiguity sets.The deterministic model is reformulated as a WDRCC optimization model for crude oil scheduling to guarantee the demand constraints hold with a desired high probability even in the worst situation in ambiguity sets.The proposed WDRCC model is transferred into an equivalent conditional value-at-risk representation and further derived as a mixed-integer nonlinear programming counterpart.Industrial case studies from a real-world refinery are conducted to show the effectiveness of the proposed method.Out-of-sample tests demonstrate that the solution of the WDRCC model is more robust than those of the deterministic model and the chance-constrained model. 展开更多
关键词 DISTRIBUTIONS Model OPTIMIZATION Crude oil scheduling Wasserstein distance Distributionally robust chance constraints
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Hypoxia-mediated programmed cell death is involved in the formation of wooden breast in broilers
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作者 Xinrui Zhang Tong Xing +2 位作者 Lin Zhang liang zhao Feng Gao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第5期1918-1931,共14页
Background Wooden breast(WB)myopathy is a common myopathy found in commercial broiler chickens worldwide.Histological examination has revealed that WB myopathy is accompanied by damage to the pectoralis major(PM)muscl... Background Wooden breast(WB)myopathy is a common myopathy found in commercial broiler chickens worldwide.Histological examination has revealed that WB myopathy is accompanied by damage to the pectoralis major(PM)muscle.However,the underlying mechanisms responsible for the formation of WB in broilers have not been fully elucidated.This study aimed to investigate the potential role of hypoxia-mediated programmed cell death(PCD)in the formation of WB myopathy.Results Histological examination and biochemical analysis were performed on the PM muscle of the control(CON)and WB groups.A significantly increased thickness of the breast muscle in the top,middle,and bottom portions(P<0.01)was found along with pathological structure damage of myofibers in the WB group.The number of capillaries per fiber in PM muscle,and the levels of p O_(2) and s O_(2) in the blood,were significantly decreased(P<0.01),while the levels of p CO_(2) and TCO_(2) in the blood were significantly increased(P<0.05),suggesting hypoxic conditions in the PM muscle of the WB group.We further evaluated the PCD-related pathways including autophagy,apoptosis,and necroptosis to understand the consequence response to enhanced hypoxic conditions in the PM muscle of birds with WB.The ratio of LC3 II to LC3 I,and the autophagy-related factors HIF-1α,BNIP3,Beclin1,AMPKα,and ULK1 at the m RNA and protein levels,were all significantly upregulated(P<0.05),showing that autophagy occurred in the PM muscle of the WB group.The apoptotic index,as well as the expressions of Bax,Cytc,caspase 9,and caspase 3,were significantly increased(P<0.05),whereas Bcl-2 was significantly decreased(P<0.05)in the WB-affected PM muscle,indicating the occurrence of apoptosis mediated by the mitochondrial pathway.Additionally,the expressions of necroptosis-related factors RIP1,RIP3,and MLKL,as well as NF-κB and the pro-inflammatory cytokines TNF-α,IL-1β,and IL-6,were all significantly enhanced(P<0.05)in the WB-affected PM muscle.Conclusions The WB myopathy reduces blood supply and induces hypoxia in the PM muscle,which is closely related to the occurrence of PCD including apoptosis,autophagy,and necroptosis within myofibers,and finally leads to abnormal muscle damage and the development of WB in broilers. 展开更多
关键词 Apoptosis Autophagy Broiler chicken HYPOXIA NECROPTOSIS Wooden breast
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Effects of nanostructuring on mechanical and tribological behaviors of FeCoNi medium-entropy alloy
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作者 Yan CHEN Heng LI +10 位作者 Si-en LI Gui-xun SUN liang zhao Chao-quan HU Wei ZHANG Guo-dong TONG Xue-gang CHEN Shuang HAN Hong-xiang ZONG Jun LI Jian-she LIAN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2024年第12期3963-3977,共15页
The effects of nanostructuring on the mechanical and dry-sliding wear behaviors of a FeCoNi medium-entropy alloy(MEA)were systematically investigated through nano-indentation and ball-on-disc wear tests.The results sh... The effects of nanostructuring on the mechanical and dry-sliding wear behaviors of a FeCoNi medium-entropy alloy(MEA)were systematically investigated through nano-indentation and ball-on-disc wear tests.The results show that reducing the grain size down into the nano-meter regime,on the one hand,significantly elevates the hardness of the FeCoNi alloy,and on the other hand,facilitates the formation of a surface oxide layer.As a result,the wear rate of the nanocrystalline(NC)FeCoNi alloy is one order of magnitude lower than its coarse-grained counterpart.The NC FeCoNi alloy also exhibits obviously enhanced wear resistance compared with conventional NC Ni and Ni-based alloys in terms of both lower wear rate and friction coefficient.Such enhancement in tribological properties mainly stems from the improved strain hardening ability,owing to the inevitable concentration heterogeneity in MEA that imposes extra resistance to dislocation motion. 展开更多
关键词 medium-entropy alloy FeCoNi alloy nanocrystalline mechanical behavior dry-sliding wear concentration undulation
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Ti_(3)C_(2)/In_(4)SnS_(8)肖特基异质结用于高效光催化生成H_(2)O_(2)和Cr(Ⅵ)还原
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作者 周彤 刘雪 +2 位作者 赵亮 乔明涛 雷琬莹 《物理化学学报》 SCIE CAS CSCD 北大核心 2024年第10期36-38,共3页
人工光合成是一种先进的技术,主要利用太阳能作为唯一驱动能源,将水和氧气转化成双氧水(H_(2)O_(2))。然而,目前常用的光催化系统的性能受制于其光吸收能力有限,载流子分离效率低以及表面反应能力弱等问题。在本文研究中,通过采用原位... 人工光合成是一种先进的技术,主要利用太阳能作为唯一驱动能源,将水和氧气转化成双氧水(H_(2)O_(2))。然而,目前常用的光催化系统的性能受制于其光吸收能力有限,载流子分离效率低以及表面反应能力弱等问题。在本文研究中,通过采用原位水热法,成功地在少层Ti_(3)C_(2)纳米片表面生长厚度为5-10 nm的立方相In_(4)SnS_(8)纳米片(Eg=2.16 eV),形成了一种具有三明治结构的Ti_(3)C_(2)/In4SnS8纳米复合材料。深入的表征结果显示此2D/2D异质结构具有紧密的界面相互作用并且形成肖特基异质结,有助于载流子快速从In_(4)SnS_(8)转移至Ti_(3)C_(2)表面。其中,7 wt%Ti_(3)C_(2)/In_(4)SnS_(8)复合材料表现出最佳的可见光催化性能,H_(2)O_(2)生成速率为1.998µmol·L^(-1)·min·1,Cr(Ⅵ)的还原速率为19.8×10^(-3)min^(-1)。通过捕获实验、气氛实验和电子顺磁共振分析,证明了H_(2)O_(2)生成的途径包括两种:一种是两步单电子还原路径,另一种是一步两电子水氧化路径。本研究为设计高效、多功能的催化体系提供了一种新的思路。 展开更多
关键词 Ti_(3)C_(2) In_(4)SnS_(8) 光催化 生成H_(2)O_(2) Cr(Ⅵ)还原
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Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization
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作者 Chenhao Wei Di Gao +3 位作者 Guohao Zhang liang zhao Jinsen Gao Chunming Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期16-26,共11页
1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and xylene.Besides,the increasing market demand of xylene has put ... 1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and xylene.Besides,the increasing market demand of xylene has put forward higher requirements for new generation of catalyst.For increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was studied.Catalysts with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and recrystallization.It was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst surface.While the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the catalyst.Besides,the state of loaded Zn was also affected by mesopores spatial distribution.On the optimized catalyst,the xylene selectivity was enhanced by 12.4%compared with conventional Zn-loaded parent HZSM-5 catalyst at conversion over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid properties.This work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst. 展开更多
关键词 1-Hexene aromatization Alkali treatment Xylene selectivity MESOPORES Zinc state
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基于MDS-YOLO模型的小目标检测问题研究
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作者 朱恩文 梁曌 +1 位作者 肖进文 梁小林 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第12期78-86,共9页
针对目前主流算法对小目标检测存在计算量大与准确率较低的问题,本文以轻量级网络MobileNetV3代替YOLOv4中的主干网络,并将颈部网络中的一部分普通卷积用深度可分离卷积替代,同时针对小目标检测定义一个新的损失函数IF-EIoU Loss,由此... 针对目前主流算法对小目标检测存在计算量大与准确率较低的问题,本文以轻量级网络MobileNetV3代替YOLOv4中的主干网络,并将颈部网络中的一部分普通卷积用深度可分离卷积替代,同时针对小目标检测定义一个新的损失函数IF-EIoU Loss,由此构建了MDSYOLO目标检测模型.该模型具有较高的检测速度,且针对小目标具有较好的检测性能.为了验证模型的有效性,分别在MS COCO数据集和Visdrone2019数据集上进行了实验.与YOLOv4算法相比,在MS COCO数据集上,MDS-YOLO算法的平均检测精度提升了1.5个百分点,对于小目标的检测精度提升了3.3个百分点,检测速度也从31帧/s提升至36帧/s;在Visdrone2019数据集上,MDS-YOLO算法将平均检测精度从YOLOv4的14.9%提升至16.3%.实验结果表明,本文提出的MDS-YOLO算法能有效提升小目标检测精度. 展开更多
关键词 小目标检测 YOLOv4算法 轻量级网络MobileNetV3 IF-EIoU Loss MS COCO数据集
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Health effects of fruit juices and beverages with varying degrees of processing
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作者 Xinyue Zhang Xiaojun Liao +2 位作者 Yongtao Wang Lei Rao liang zhao 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第5期2456-2479,共24页
The degree of processing is rarely considered an independent factor in the health effects of fruit juices and beverages(FJBs)consumption.In fact,the consumption of ultra-processed foods has been shown to pose health r... The degree of processing is rarely considered an independent factor in the health effects of fruit juices and beverages(FJBs)consumption.In fact,the consumption of ultra-processed foods has been shown to pose health risks.In this study,we first integrated 4 systems used to classify the degree of food processing and then classified FJBs into three major categories,low(minimal),moderate and high.Second,we compared the differences in attitudes towards FJBs in dietary guidelines.Third,we integrated the results of existing epidemiological surveys,randomized controlled trials,and animal experiments to explore the health risks associated with consuming FJBs.Deepening the processing of FJBs has been found to lead to an increased risk of diseases.Dietary pattern,nutrients,addition agents and consumer preferences may be influential factors.Finally,we investigated whether there were any changes in the health benefits of 100%fruit juices produced by different processing methods.In conclusion,minimally/moderately processed 100%fruit juices provide more health benefits than highly processed fruit beverages.The results support the need to consider the extent of FJBs processing in future studies to adjust official nutritional recommendations for beverage consumption. 展开更多
关键词 Fruit juices and beverages Dietary guidelines Degree of processing Health effects MECHANISM
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Tracing the sources of nutrients through the Tsushima/Korea Strait
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作者 Jing Zhang Xinyu Guo +2 位作者 Lei Zhu Jianlong Feng liang zhao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第6期142-152,共11页
The nutrients from the East China Sea(ECS) through the Tsushima/Korea Strait(TS) strongly impact the eco system of the Japan Sea(JS).The complex origins of the Tsushima Warm Current and the various nutrient sources in... The nutrients from the East China Sea(ECS) through the Tsushima/Korea Strait(TS) strongly impact the eco system of the Japan Sea(JS).The complex origins of the Tsushima Warm Current and the various nutrient sources in the ECS result in complex spatial-temporal variations in nutrients in the TS.Using a physical-biological model with a tracking technique,we studied the effects of nutrient sources from the ECS on the TS.Among all the nutrient sources,the Kuroshio has the highest nutrient concentrations in the TS.Its maximum concentration occurs at the bottom,while those of rivers and atmospheric depo sition occur at the surface,and that of the Taiwan Strait occurs in the middle layer.The nutrient transport through the TS exhibits similar seasonal variations,as does the volume transport.The transport of nutrients from the Kuroshio accounts for more than 85% of the total.The transport of nutrients from the Taiwan Strait is greater during autumn and winter.The transport of dissolved inorganic nitrogen(DIN) from both rivers and atmospheric deposition through the TS peak in August.Nutrient transport cannot be equated with volume transport.The DIN in the less saline zone originates not only from rivers but also from atmospheric deposition and the Kuroshio.The transport of nutrients from the Taiwan Strait is not as significant as its volume transport in the TS. 展开更多
关键词 dissolved inorganic nitrogen dissolved inorganic phosphate East China Sea Japan Sea nutrient transport
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Ascending phase of solar cycle 25 tilts the current El Nino-Southern oscillation transition
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作者 Wenjuan Huo Ziniu Xiao +1 位作者 liang zhao Fei Liu 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期34-38,共5页
自2020年初夏,赤道太平洋地区出现拉尼娜现象并持续两年半多(以下简称2020拉尼娜),对其未来演变的预测引起了很多关注,考虑到11年太阳周期活动对热带太平洋SST异常可能存在锁相影响,本研究分析了当前太阳活动周(即第25太阳周(SC25))对... 自2020年初夏,赤道太平洋地区出现拉尼娜现象并持续两年半多(以下简称2020拉尼娜),对其未来演变的预测引起了很多关注,考虑到11年太阳周期活动对热带太平洋SST异常可能存在锁相影响,本研究分析了当前太阳活动周(即第25太阳周(SC25))对目前热带太平洋ENSO现象未来演变的调节作用,基于历史太阳周的统计特征,作者对第25太阳周达到其最大值的时间提出三种可能的情景,并讨论了不同情景下的太阳活动对未来两年ENSO演变的可能影响,第25太阳周的持续上升阶段在一定程度上抑制了当前2023厄尔尼诺现象发展为超级事件. 展开更多
关键词 厄尔尼诺-南方涛动 太阳活动 热带太平洋 位相转变 预测 三重拉尼娜现象
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Computational fluid dynamics modeling of rapid pyrolysis of solid waste magnesium nitrate hydrate under different injection methods
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作者 Wenchang Wu Kefan Yu +1 位作者 liang zhao Hui Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期224-237,共14页
This study developed a numerical model to efficiently treat solid waste magnesium nitrate hydrate through multi-step chemical reactions.The model simulates two-phase flow,heat,and mass transfer processes in a pyrolysi... This study developed a numerical model to efficiently treat solid waste magnesium nitrate hydrate through multi-step chemical reactions.The model simulates two-phase flow,heat,and mass transfer processes in a pyrolysis furnace to improve the decomposition rate of magnesium nitrate.The performance of multi-nozzle and single-nozzle injection methods was evaluated,and the effects of primary and secondary nozzle flow ratios,velocity ratios,and secondary nozzle inclination angles on the decomposition rate were investigated.Results indicate that multi-nozzle injection has a higher conversion efficiency and decomposition rate than single-nozzle injection,with a 10.3%higher conversion rate under the design parameters.The decomposition rate is primarily dependent on the average residence time of particles,which can be increased by decreasing flow rate and velocity ratios and increasing the inclination angle of secondary nozzles.The optimal parameters are injection flow ratio of 40%,injection velocity ratio of 0.6,and secondary nozzle inclination of 30°,corresponding to a maximum decomposition rate of 99.33%. 展开更多
关键词 MULTI-NOZZLE Computational fluid dynamics Thermal decomposition reaction Pyrolysis furnace
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海上拌合平台设计与施工关键技术
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作者 梁招 陈言 +2 位作者 雷栋 金磊 罗鹏 《施工技术(中英文)》 CAS 2024年第12期125-129,共5页
结合舟岱跨海大桥工程施工特点,设计了一种全“装配化桩式型钢”拌合平台,在其上设置混凝土拌合站,实现离岸工程混凝土持续供应,并运用空间有限元计算软件MIDAS/Civil对拌合平台进行力学性能分析,在浪流作用下,水平侧向位移小,结构整体... 结合舟岱跨海大桥工程施工特点,设计了一种全“装配化桩式型钢”拌合平台,在其上设置混凝土拌合站,实现离岸工程混凝土持续供应,并运用空间有限元计算软件MIDAS/Civil对拌合平台进行力学性能分析,在浪流作用下,水平侧向位移小,结构整体安全。在海上拌合平台应用中,总结一些具有实际工程意义的施工关键技术。 展开更多
关键词 桥梁工程 混凝土 拌合平台 装配式 设计 筒仓 施工技术 有限元分析
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主编的话
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作者 赵亮 《城市设计》 2024年第1期3-3,共1页
随着我国城市建设从大规模新区拓展逐步进入到城市存量更新的新阶段,TOD项目在策划、规划、设计和实施过程中面临尤为复杂的财务、产权、多部门协同等现实问题,同时在以人为本、低碳绿色的高质量城市空间方面需要实现更高的目标。本期... 随着我国城市建设从大规模新区拓展逐步进入到城市存量更新的新阶段,TOD项目在策划、规划、设计和实施过程中面临尤为复杂的财务、产权、多部门协同等现实问题,同时在以人为本、低碳绿色的高质量城市空间方面需要实现更高的目标。本期以“城市更新背景下的TOD”为主题,收录10篇论文,选题涉及城市、线路、站点3个层面,包含TOD相关规程、精细化和多部门协同的规划设计实践、人本和低碳的量化分析方法等。 展开更多
关键词 规划设计 存量更新 TOD 精细化 低碳绿色 多部门协同 以人为本 量化分析方法
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基于政策法规数据的嵌套命名实体识别研究
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作者 徐晗 梁曌 梁小林 《湖南文理学院学报(自然科学版)》 CAS 2024年第3期19-23,29,共6页
针对政策法规文本数据中常常出现的嵌套实体问题进行了分析,构建了一个融合双仿射变换的指针网络模型。该模型使用指针网络替代传统的条件随机场模型来降低计算复杂度,配合双仿射变换模块解决嵌套实体问题,同时定义了一个新的损失函数... 针对政策法规文本数据中常常出现的嵌套实体问题进行了分析,构建了一个融合双仿射变换的指针网络模型。该模型使用指针网络替代传统的条件随机场模型来降低计算复杂度,配合双仿射变换模块解决嵌套实体问题,同时定义了一个新的损失函数解决命名实体的稀疏性问题。实验结果表明,该模型改善了传统组合模型在政策法规数据上出现的过拟合及实际预测效果欠佳的问题,在自建政策法规数据中取得了较好的结果,F1得分达到了78.41%,相对传统方法提升明显。 展开更多
关键词 命名实体识别 政策文本挖掘 嵌套实体 自然语言处理 Bert-BiLSTM-Biaffine-Span模型
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Ethnic Customs and Rural Tourism Development in Xinbin Manchu Autonomous County of Fushun City
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作者 Siyu WANG liang zhao 《Asian Agricultural Research》 2024年第5期8-10,共3页
The development of ethnic minority tourism is currently a hot topic in domestic tourism development.As an important component of Chinese civilization,the Manchu people have created brilliant culture in the long river ... The development of ethnic minority tourism is currently a hot topic in domestic tourism development.As an important component of Chinese civilization,the Manchu people have created brilliant culture in the long river of historical development.As the hometown of the Manchu people,Fushun has unique folk cultural tourism resources and a strong ethnic flavor.Nowadays,under the promotion of the rural revitalization strategy,the construction of new rural areas is constantly developing,and rural tourism is gradually becoming a new industry.Therefore,in the context of the increasingly prosperous rural tourism industry,it has become increasingly important to combine the ethnic customs of Manchu culture with rural tourism.Taking the ethnic customs and integrated development of rural tourism in Xinbin Manchu Autonomous County of Fushun City,Liaoning Province as the research object,this paper mainly sorts out the current situation and characteristics of rural tourism development in the region,systematically explores the problems in development and how to further optimize development,and proposes new models suitable for the development of folk tourism in Xinbin of Fushun,in order to achieve maximum economic and social benefits and provide a reference for promoting the development of tourism in the region. 展开更多
关键词 Xinbin Manchu Autonomous County Manchu ethnic customs Rural revitalization Rural tourism development
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