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Seasonal variation and sources of atmospheric polycyclic aromatic hydrocarbons in a background site on the Tibetan Plateau

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Journal of Environmental Sciences 2023年第3期125卷 524-532页

作者： Xuemei Wu weijun sun Baojuan Huai LeiWang Chuntan Han Yetang Wang Wenying Mi College of Geography and Environment Shandong Normal UniversityJinan 250014China Qilian Alpine Ecology and Hydrology Research Station Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China MINJIE Institute of Environmental Science and Health Research Geesthacht 21502Germany

The study of atmospheric polycyclic aromatic hydrocarbons(PAHs) in northeastern Tibetan Plateau with fragile ecological environment and complex atmospheric circulation system is blank. To understand the characteristics and sources of persistent organic pollutants in the atmosphere of the northeastern Tibetan Plateau, we monitored levels in the central Qilian Mountain. From 2016 to 2017, we collected 45-pair(particle + gas) samples using active air samplers to investigate the sources, transport paths, and their influencing *** of PAHs were analysed with a source diagnostic model, and atmospheric transport paths were calculated. The concentration range for Σ15PAHs was 439–4666 pg/m^(3), and the average was 2015 pg/m^(3). The PAHs in central Qilian Mountain are mainly low molecular weight(LMW) PAHs. Winter concentrations of PAHs were higher than those in summer. The transport of PAHs is mainly affected by westerlies, and there are seasonal differences. Source analysis showed that PAHs mainly came from coal and biomass combustion and vehicle emissions, with seasonal differences. This study clarifies the concentration and seasonal variation of PAHs in the northern Tibetan Plateau, which is conducive to understanding the atmospheric transport process and fate of pollutants. The background site of Qilian Mountains located in the Silk Road economic belt has the value and significance of longterm observation of pollutants.

关键词： Long-range atmospheric transport Seasonal variation concentration Meteorological factors Qilian Mountain

How do GPM and TRMM precipitation products perform in alpine regions?A case study in northwestern China's Qilian Mountains

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Journal of Geographical Sciences 2022年第5期32卷 913-931页

作者： sun weijun CHEN Rensheng WANG Lei WANG Yingshan HAN Chuntan HUAI Baojuan College of Geography and Environment Shandong Normal UniversityJinan250358China Qilian Alpine Ecology&Hydrology Research Station Key Laboratory of Ecohydrology of Inland River BasinNorthwest Institute of Eco-Environment and ResourcesCASLanzhou730000China

Satellite technologies provide valuable areal precipitation datasets in alpine ***,coarse resolution still limits the use of satellite precipitation datasets in hydrological and meteorological *** evaluated different time scales and precipitation magnitudes of Tropical Rainfall Measurement Mission 3B43 V7(TRMM)and Global Precipitation Measurement(GPM)products for alpine regions using ground precipitation datasets from January 2015 to June 2019 obtained from 25 national meteorological stations and 11 sets of T-200B weighing precipitation gauges in the Qilian *** results indicated that GPM outperformed TRMM at all temporal scales at an elevation3500 m,with the best performance at 4000 *** and TRMM had the best estimation accuracy in areas with monthly precipitation of 30 mm and 40 mm,*** TRMM and GPM products underestimated mid to large daily precipitation and overestimated light daily precipitation averaging<2 mm/*** research not only emphasizes the superiority of GPM/TRMM in different regions but also indicates the limitations of precipitation algorithms.

关键词： accuracy assessment GPM TRMM alpine regions precipitation

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助残抓取柔性外手指结构设计及抓取实验

轻工机械 2024年第3期42卷 20-28页

作者：郭书言许勇孙伟军刘凌霄上海工程技术大学机械与汽车工程学院上海201620

为了解决上肢损伤患者所采用的协同和康复机构较为繁杂且昂贵的问题,课题组提出了一种可穿戴柔性外手指系统,能够与伤残手臂协同动作进行抓取。设计了欠驱动外手指本体结构,通过使用柔性关节减少了驱动器数量、结构质量及机构复杂性,同... 详细信息

为了解决上肢损伤患者所采用的协同和康复机构较为繁杂且昂贵的问题,课题组提出了一种可穿戴柔性外手指系统,能够与伤残手臂协同动作进行抓取。设计了欠驱动外手指本体结构,通过使用柔性关节减少了驱动器数量、结构质量及机构复杂性,同时使外手指获得了对不同外形及尺寸物体的抓取适应性;建立了外手指包络抓取过程的运动学和静力学模型;设计了外手指系统样机本体及驱动、控制模块;进行了弯曲运动仿真和样机抓取实验。仿真和实验结果表明该外手指系统能够稳定地实现对不同外形物体的包络抓取运动。该柔性外手指理论建模和结构设计具有合理性,有助于上肢损伤患者对物品进行抓取。

关键词：可穿戴机器人外手指欠驱动结构柔性关节包络抓取

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颗粒阻塞变刚度可折叠柔性臂设计

轻工机械 2024年第1期42卷 27-35页

作者：许勇郭书言孙伟军刘凌霄丁睿杜静恩上海工程技术大学机械与汽车工程学院上海201620 上海工程技术大学材料科学与工程学院上海201620

针对折纸结构存在的刚度恒定不变及刚度不足难题,基于折纸结构和颗粒阻塞原理,笔者提出一种质量小、惯量低、刚度调节范围宽、空间折展比大、制作成本低的变刚度可折叠柔性操作臂。首先,设计了由多个折叠柔性单元串联而成的折叠柔性臂... 详细信息

针对折纸结构存在的刚度恒定不变及刚度不足难题,基于折纸结构和颗粒阻塞原理,笔者提出一种质量小、惯量低、刚度调节范围宽、空间折展比大、制作成本低的变刚度可折叠柔性操作臂。首先,设计了由多个折叠柔性单元串联而成的折叠柔性臂的三维结构方案;提出基于颗粒阻塞原理的折叠柔性臂的刚度调节方法,完成了柔性臂变刚度系统方案设计;提出电机驱动、绳索传动的折叠柔性臂驱动方案,以实现柔性臂的位姿变换;最后,完成变刚度折叠柔性臂的样机制作和弯曲变形实验、刚度测试实验测试。样机实验测试结果表明:所提出颗粒阻塞变刚度可折叠柔性臂的弯曲实验结果与运动学模型、刚度模型的理论计算结果较为一致,验证了该变刚度柔性臂的设计方案的正确性。

关键词：柔性臂折纸结构折叠柔性单元变刚度颗粒阻塞

FAPI PET/CT在消化道肿瘤诊断中的研究进展

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温州医科大学学报 2024年第2期54卷 158-164页

作者：金景国王志强孙卫军徐慧章万乐温州医科大学附属第一医院核医学科浙江温州325015

核医学放射性药物是一种利用放射性同位素标记化合物作为特定生物或器官成像和治疗的工具。同位素标记的成纤维细胞活化蛋白抑制剂(FAPI)是一种新型的放射性药物,具有高灵敏度和特异度,能够提供高分辨率的图像,准确检测和定位肿瘤,评估... 详细信息

核医学放射性药物是一种利用放射性同位素标记化合物作为特定生物或器官成像和治疗的工具。同位素标记的成纤维细胞活化蛋白抑制剂(FAPI)是一种新型的放射性药物,具有高灵敏度和特异度,能够提供高分辨率的图像,准确检测和定位肿瘤,评估其生长和转移情况,以及检测治疗效果;并且能提供关于肿瘤组织的详细信息,有助于制定个体化治疗方案,已被广泛研究和应用于多种癌症的诊断和治疗。笔者将介绍FAPI的特点及FAPI PET/CT在消化道肿瘤中的应用,并比较其和18F-FDG PET/CT在消化道肿瘤诊断中的优劣情况,以进一步说明FAPI在消化道肿瘤中的应用价值。

关键词：消化道肿瘤成纤维细胞活化蛋白抑制剂氟脱氧葡萄糖F18 正电子发射断层显像术

Learning to represent 2D human face with mathematical model

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 54-68页

作者： Liping Zhang weijun Li Linjun sun Lina Yu Xin Ning Xiaoli Dong AnnLab Institute of SemiconductorsChinese Academy of SciencesBeijingChina Center of Materials Science and Optoelectronics Engineering School of Integrated CircuitsUniversity of Chinese Academy of SciencesBeijingChina Beijing Key Laboratory of Semiconductor Neural Network Intelligent Sensing and Computing Technology BeijingChina

How to represent a human face pattern?While it is presented in a continuous way in human visual system,computers often store and process it in a discrete manner with 2D arrays of *** authors attempt to learn a continuous surface representation for face image with explicit ***,an explicit model(EmFace)for human face representation is pro-posed in the form of a finite sum of mathematical terms,where each term is an analytic function ***,to estimate the unknown parameters of EmFace,a novel neural network,EmNet,is designed with an encoder-decoder structure and trained from massive face images,where the encoder is defined by a deep convolutional neural network and the decoder is an explicit mathematical expression of *** authors demonstrate that our EmFace represents face image more accurate than the comparison method,with an average mean square error of 0.000888,0.000936,0.000953 on LFW,IARPA Janus Benchmark-B,and IJB-C *** results show that,EmFace has a higher representation performance on faces with various expressions,postures,and other ***,EmFace achieves reasonable performance on several face image processing tasks,including face image restoration,denoising,and transformation.

关键词： artificial neural networks face analysis image processing mathematics computing

Investigating the Impact of Ocean Acidification on Anti-Stress Mechanisms in Sepia esculenta Larvae Based on Transcriptome Profiling

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JOURNAL OF OCEAN UNIVERSITY OF CHINA 2024年第4期23卷 1054-1066页

作者： Wang, Yongjie Liu, Xiumei Lv, Tingjin Wang, weijun sun, Guohua Yang, Jianmin Li, Zan Ludong Univ Sch Agr Yantai 264025 Peoples R China Yantai Univ Coll Life Sci Yantai 264005 Peoples R China Yantai Inst Marine Econ Yantai 264003 Peoples R China

With the rapid development of oil, energy, power and other industries, CO2 emissions rise sharply, which will cause a large amount of CO2 in the air be absorbed by the ocean and lead to ocean acidification. The growth and development of organisms can be seriously affected by acidified seawater. Sepia esculenta is a mollusk with high nutritional and economic value and is widely cultured in offshore waters of China. Larvae are the early life forms of the organism and are more vulnerable to changes in the external environment. Too low pH will lead to some adverse reactions in larvae, which will affect metabolism, immune response and other life activities. In this study, we sequenced the transcriptome of S. esculenta subjected to acidified seawater stress and identified 1072 differentially expressed genes (DEGs). The detected atypical expression of DEGs substantiates cellular malformation and translocation in S. esculenta under low pH stimulation. Simultaneously, this also substantiates the notable impact of ocean acidification on mollusks. These DEGs were used for functional enrichment analysis of GO and KEGG, and the top twenty items of the biological process classification in GO terms and 11 KEGG signaling pathways were significantly enriched. Finally, the constructed protein-protein interaction network (PPI) was used to analyze protein-protein interactions, and 12 key DEGs and 3 hub genes were identified. The reliability of 12 genes was verified by quantitative RT-PCR. A comprehensive analysis of the KEGG signaling pathway and PPI revealed that ocean acidification leads to abnormalities in lipid metabolism in S. esculenta larvae, which can lead to cancer development and metastasis, accompanied by some degree of inflammation. The results of the study will help to further investigate the physiological processes of S. esculenta when stimulated by ocean acidification, and provide a reference to cope with the captive breeding of S. esculenta affected by acidification.

关键词： Sepia esculenta ocean acidification protein-protein interaction network transcriptome immunity METABOLISM EXPRESSION ROLES

基于LICOR-830与Picarro G2301的温室气体分析仪精度对比研究

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山东师范大学学报（自然科学版） 2024年第1期39卷 52-61页

作者：南瑞琪田彪孙维君朱孔驹张文千汤洁丁明虎山东师范大学地理与环境学院济南250358 中国气象科学研究院全球变化与极地研究所北京100081

在应对气候变化和实现“双碳”战略过程中,需要对温室气体进行高精度的观测,而目前在实验室关于量化不同观测系统精度差异的研究相对较少。本研究选择基于非色散红外吸收法的LICOR-830型CO_(2)气体分析仪与基于光腔衰荡光谱法的Picarro ... 详细信息

在应对气候变化和实现“双碳”战略过程中,需要对温室气体进行高精度的观测,而目前在实验室关于量化不同观测系统精度差异的研究相对较少。本研究选择基于非色散红外吸收法的LICOR-830型CO_(2)气体分析仪与基于光腔衰荡光谱法的Picarro G2301型CO_(2)/CH4/H2O气体分析仪,对3种CO_(2)可溯源标气进行观测,开展重复性测试、漂移测试和目标标气测试,并对观测浓度进行精度对比分析。测试结果为1)重复性测试:LICOR-830的精度约为0.4 ppm,Picarro G2301的精度约为0.04 ppm,两者精度相差一个数量级;2)漂移测试:LICOR-830准确度为-4.22%,Picarro G2301准确度为0.82%,两者准确度相差5倍;3)目标标气测试:用3种浓度的标气对实测浓度进行1 h的校正后,LICOR-830精度提升15倍,达到0.026 ppm,准确度为-0.11%,Picarro G2301的精度略有提升,达到0.0341 ppm,准确度为0.03%。结果显示,LICOR-830的精度水平在校正后可满足WMO对CO_(2)观测的精度要求,具有较大的应用潜力。

关键词： LICOR-830 Picarro G2301 温室气体精度对比

Approximately orthogonal nonnegative Tucker decomposition for flexible multiway clustering

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Science China(Technological Sciences) 2021年第9期64卷 1872-1880页

作者： QIU YiChun sun weijun ZHANG Yu GU XiaoBo ZHOU GuoXu School of Automation Guangdong University of TechnologyGuangzhou 510006China Key Laboratory of Intelligent Detection and The Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China Department of Bioengineering Lehigh UniversityBethlehemPA 18015USA Guangdong-Hong Kong-Macao Joint Laboratory for Smart Manufacturing Guangzhou 510006China Guangdong Key Laboratory of IoT Information Technology Guangzhou 510006China

High-order tensor data are prevalent in real-world applications, and multiway clustering is one of the most important techniques for exploratory data mining and compression of multiway data. However, existing multiway clustering is based on the K-means procedure and is incapable of addressing the issue of crossed membership degrees. To overcome this limitation, we propose a flexible multiway clustering model called approximately orthogonal nonnegative Tucker decomposition(AONTD). The new model provides extra flexibility to handle crossed memberships while fully exploiting the multilinear property of tensor *** accelerated proximal gradient method and the low-rank compression tricks are adopted to optimize the cost function. The experimental results on both synthetic data and real-world cases illustrate that the proposed AONTD model outperforms the benchmark clustering methods by significantly improving the interpretability and robustness.

关键词： multiway data analysis nonnegative Tucker decomposition flexible clustering accelerated proximal gradient