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定量转换函数在人类世湖泊水环境变化研究中的应用

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地球科学进展 2024年第5期39卷 504-518页

作者：孙信尧张科林琪沈吉南京大学地理与海洋科学学院江苏南京210023 中国科学院南京地理与湖泊研究所湖泊与流域水安全重点实验室江苏南京210008

近现代(1950年)以来,全球湖泊系统普遍面临水生态环境挑战,利用转换函数可定量重建湖泊水环境自然基线和演化历史,评估人类活动的影响程度并为生态修复提供合理目标。从转换函数构建及应用的基本流程入手,围绕pH值、总磷、溶氧量、透明... 详细信息

近现代(1950年)以来,全球湖泊系统普遍面临水生态环境挑战,利用转换函数可定量重建湖泊水环境自然基线和演化历史,评估人类活动的影响程度并为生态修复提供合理目标。从转换函数构建及应用的基本流程入手,围绕pH值、总磷、溶氧量、透明度、水位、盐度和温度这几种水环境参数,综合梳理了生物—湖泊水环境定量转换函数在人类世湖泊流域中的典型应用案例,从不同角度考察了湖泊自然水生态环境受人类扰动而发生改变的速率、幅度以及演化过程与机制。最后,讨论了定量转换函数方法目前存在的不足,并从新载体开发和多指标体系构建、大样本训练集和机器学习、加强生物指标的现代生态学研究以及转换函数与生态系统模型的结合4个方面,针对性地提出几点展望,以进一步提升转换函数性能,并扩大其应用范围,为后续研究提供参考。

关键词：湖泊水环境湖泊沉积转换函数定量重建环境演化人类世

Prediction-based Manufacturing Center Self-adaptive Demand Side Energy Optimization in Cyber Physical Systems

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Chinese Journal of Mechanical Engineering 2014年第3期27卷 488-495页

作者： sun xinyao WANG Xue WU Jiangwei LIU Youda State Key Laboratory of Precision Measurement Technology and Instrument Tsinghua University

Cyber physical systems（CPS） recently emerge as a new technology which can provide promising approaches to demand side management（DSM）, an important capability in industrial power systems. Meanwhile, the manufacturing center is a typical industrial power subsystem with dozens of high energy consumption devices which have complex physical dynamics. DSM, integrated with CPS, is an effective methodology for solving energy optimization problems in manufacturing center. This paper presents a prediction-based manufacturing center self-adaptive energy optimization method for demand side management in cyber physical systems. To gain prior knowledge of DSM operating results, a sparse Bayesian learning based componential forecasting method is introduced to predict 24-hour electric load levels for specific industrial areas in China. From this data, a pricing strategy is designed based on short-term load forecasting results. To minimize total energy costs while guaranteeing manufacturing center service quality, an adaptive demand side energy optimization algorithm is presented. The proposed scheme is tested in a machining center energy optimization experiment. An AMI sensing system is then used to measure the demand side energy consumption of the manufacturing center. Based on the data collected from the sensing system, the load prediction-based energy optimization scheme is implemented. By employing both the PSO and the CPSO method, the problem of DSM in the manufac^ring center is solved. The results of the experiment show the self-adaptive CPSO energy optimization method enhances optimization by 5% compared with the traditional PSO optimization method.

关键词： cyber physical systems manufacturing center self-adaptive demand side management particle swarm optimization

PET影像组学在消化系统肿瘤诊疗中的研究进展

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中国医学影像学杂志 2024年第4期32卷 407-416页

作者：黄文鹏邱永康宋乐乐杨琦孙昕瑶王天尧康磊北京大学第一医院核医学科北京100034

影像组学采用医工相结合的方式,将传统图像转化为高维度、深层次的数字定量特征,挖掘图像的潜在生物标志物和异质性。消化系统恶性肿瘤在中国的发病率和死亡率均较高,近年来在人工智能发展和大数据时代的推动下,PET影像组学应用发展迅速... 详细信息

影像组学采用医工相结合的方式,将传统图像转化为高维度、深层次的数字定量特征,挖掘图像的潜在生物标志物和异质性。消化系统恶性肿瘤在中国的发病率和死亡率均较高,近年来在人工智能发展和大数据时代的推动下,PET影像组学应用发展迅速,并在消化系统肿瘤的诊断、鉴别、疗效及预后评估等方面取得了一些有前景的研究成果,向无创性精确医学分析迈进。本文对PET影像组学在消化系统肿瘤中的诊疗进展进行综述,并分析面临的挑战与展望。

关键词：消化系统肿瘤正电子发射断层显像术影像组学综述

维普期刊数据库博看期刊

Screening non-noble metal oxides to boost the low-temperature combustion of polyethylene waste in air

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Chinese Journal of Chemical Engineering 2023年第6期58卷 155-162页

作者： xinyao sun Liu Zhao Xu Hou Hao Zhou Huimin Qiao Chenggong Song Jing Huang Enxian Yuan School of Chemical Engineering Changchun University of TechnologyChangchun 130012China Advanced Institute of Materials Science Changchun University of TechnologyChangchun 130012China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China

Globally,the efficient utilization of polymer wastes is one of the most important issues for current sustainable development ***,a green and efficient low-temperature combustion approach is proposed to deal with polymer wastes and recover heat energy,simultaneously alleviating the environment and energy ***-noble metal oxides(Al_(2)O_(3),Fe_(2)O_(3),NiO_(2),ZrO_(2),La_(2)O_(3)and CeO_(2)) were prepared,characterized and screened to boost the low-temperature combustion of polyethylene waste at 300℃ in *** mass change,heat release and CO_(x) formation were studied in details and employed to evaluate the combustion rate and *** was found that CeO_(2)significantly enhanced the combustion rate and efficiency,which was respectively 2 and 7 times that of non-catalytic *** interesting phenomenon was observed that the catalytic performance of CeO_(2) in polyethylene low-temperature combustion was significantly improved by the 7-day storage in the room environment or water *** analysis confirmed the co-existence of Ce^(3+) and Ce^(4+) in CeO_(2),and the 7-day storage and water treatment promoted the amount of Ce^(3+),which facilitated the formation of the oxygen *** may be the reason why CeO_(2) exhibited excellent catalytic performance in polyethylene low-temperature combustion.

关键词： Polymer wastes Low-temperature combustion Metal oxides CeO_(2)

MOFs基固体电解质在钠离子电池中的应用进展

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化工新型材料 2024年第5期52卷 21-26页

作者：周志远王春梅张嘉孙鑫垚张瑶丁大千高艳芳内蒙古工业大学化工学院呼和浩特010010 大规模储能技术教育部工程研究中心呼和浩特010010

传统钠离子电池常使用液体有机电解质,存在热失控等安全问题。而固态电解质具有高安全性和高能量密度,因而成为下一代储能设备材料最有潜力的候选者。金属有机骨架(MOFs)由金属节点和有机连接器构成,具有高孔隙率、高比表面积和有序孔道... 详细信息

传统钠离子电池常使用液体有机电解质,存在热失控等安全问题。而固态电解质具有高安全性和高能量密度,因而成为下一代储能设备材料最有潜力的候选者。金属有机骨架(MOFs)由金属节点和有机连接器构成,具有高孔隙率、高比表面积和有序孔道,是设计快速离子导电材料的一个很有前途的结构平台。基于MOFs结构的多样性和可修饰性,介绍几种导钠离子MOFs基固体电解质的研究设计,包括引入掺杂相应阴离子钠盐的离子液体或有机溶剂、钠化处理、枝接与电解质离子相互作用的官能团和与聚合物复合的杂化材料。

关键词：固态钠离子电池金属有机骨架固体电解质离子电导率

Yr5-virulent races of Puccinia striiformis *** possess relative parasitic fitness higher than current main predominant races and potential risk

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Journal of Integrative Agriculture 2024年第8期23卷 2674-2685页

作者： Gensheng Zhang Mudi sun xinyao Ma Wei Liu Zhimin Du Zhensheng Kang Jie Zhao State Key Laboratory of Crop Resistance and High-Efficiency Production College of Plant ProtectionNorthwest A&F UniversityYangling 712100China

Wheat stripe rust,caused by Puccinia striiformis ***(Pst),is one of the most destructive fungal diseases of wheat,and seriously threatens safe production of the crop *** China,new races historically appeared and rapidly developed to be predominant races and have resulted in ineffectiveness and replacement of wheat resistance cultivars as well as massive reduction in *** the present study,the relative parasitic fitness of the two newlyemerged Yr5-virulent races(TSA-6 and TSA-9)were compared with those of four currently predominant Chinese races(CYR31,CYR32,CYR33,and CYR34)based on evaluation on 10 Chinese wheat *** a result,there were significant differences in the relative parasitic fitness parameters among overall tested races based on multiple comparison(LSD)analysis(PTSA-9(0.95)>TSA-6(0.92)>CYR34(0.29)>CYR31(–1.54)>CYR33(–1.77).The results indicated that two Yr5-virulent races TSA-9 and TSA-6 possessed relative parasitic fitness higher than races CYR34,CYR31,and CYR33,but lower than race CYR32,and have potential risks in developing to be predominant ***,continual monitoring of both Yr5-virulent races,and their variants is *** use of wheat cultivars(lines)with Yr5 resistance gene singly in wheat breeding is essential for being avoided,and is suggested to combine with other effective stripe rust resistance genes.

关键词： wheat stripe rust Puccinia striiformis f.sp.tritici parasitic fitness Yr5 new race

Effect of bubble morphology and behavior on power consumption in non-Newtonian fluids’aeration process

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Chinese Journal of Chemical Engineering 2024年第1期65卷 243-254页

作者： Xiemin Liu Jing Wan Jinnan sun Lin Zhang Feng Zhang Zhibing Zhang xinyao Li Zheng Zhou Key Laboratory of Mesoscopic Chemistry of Ministry of Education(MOE) School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Dalian Research Institute of Petroleum and Petrochemicals SINOPECDalian 116045China

Due to a prolonged operation time and low mass transfer efficiency, the primary challenge in the aeration process of non-Newtonian fluids is the high energy consumption, which is closely related to the form and rate of impeller, ventilation, rheological properties and bubble morphology in the reactor. In this perspective, through optimal computational fluid dynamics models and experiments, the relationship between power consumption, volumetric mass transfer rate(kLa) and initial bubble size(d0) was constructed to establish an efficient operation mode for the aeration process of non-Newtonian fluids. It was found that reducing the d0could significantly increase the oxygen mass transfer rate, resulting in an obvious decrease in the ventilation volume and impeller speed. When d0was regulated within 2-5 mm,an optimal kLa could be achieved, and 21% of power consumption could be saved, compared to the case of bubbles with a diameter of 10 mm.

关键词： Non-Newtonian fluids aeration process Power consumption Volumetric mass transfer rate Bubble size

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基于稀疏信号重构的无线传感网络目标定位

仪器仪表学报 2012年第2期33卷 362-368页

作者：王勇王雪孙欣尧清华大学精密仪器与机械学系精密测试技术及仪器国家重点实验室北京100084

提出了一种新的基于稀疏信号重构的无线传感网络目标定位方法。针对目标定位问题,将多目标位置表示为离散化测量空间上的稀疏向量,则多传感节点声音信号能量测量值向量可分解为测量矩阵、稀疏矩阵与稀疏向量的乘积,通过稀疏信号重构方... 详细信息

提出了一种新的基于稀疏信号重构的无线传感网络目标定位方法。针对目标定位问题,将多目标位置表示为离散化测量空间上的稀疏向量,则多传感节点声音信号能量测量值向量可分解为测量矩阵、稀疏矩阵与稀疏向量的乘积,通过稀疏信号重构方法可以恢复目标位置稀疏向量,实现多目标定位。传统L1范数稀疏信号重构法要求测量矩阵和稀疏矩阵乘积满足受限等距性条件,在目标定位问题中难以满足。采用贪婪匹配追踪算法重构稀疏向量,基于噪声信号能量幅值终止迭代搜索,进行多目标定位。实验表明,基于贪婪匹配追踪稀疏信号重构目标定位方法能准确实现多目标定位,定位精度优于基于正交匹配追踪的稀疏信号重构目标定位方法和基于单纯形搜索的最大似然估计目标定位方法。

关键词：稀疏信号重构目标定位压缩测量无线传感网络

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采用二次经验模态筛选的谐波辨识方法

仪器仪表学报 2012年第11期33卷 2401-2406页

作者：吴江伟王雪孙欣尧清华大学精密仪器与机械学系精密测试技术及仪器国家重点实验室北京100084

谐波辨识研究在智能电网发展中占有重要的地位,采用传统Hilbert-Huang变换(Hilbert-Huang transform,HHT)对该类非稳态信号进行处理时,会产生模态混叠、端点效应等影响信号分析精度的问题。针对此情况,提出一种模态筛选算法,采用屏蔽信... 详细信息

谐波辨识研究在智能电网发展中占有重要的地位,采用传统Hilbert-Huang变换(Hilbert-Huang transform,HHT)对该类非稳态信号进行处理时,会产生模态混叠、端点效应等影响信号分析精度的问题。针对此情况,提出一种模态筛选算法,采用屏蔽信号(masking signal)与原扰动信号叠加实现对模态混叠的抑制,通过端点非镜面对称延拓消减Hilbert变换(Hilbert transform,HT)后的端点"飞翼",并提出二次经验模态筛选算法来提高固有模态函数(intrinsic mode functions,IMFs)中所含频率的唯一性,从而改善对非稳态信号的分析精度。稳态和非稳态信号谐波辨识实验验证了该算法在谐波辨识中具有很高的抗干扰性和准确性。

关键词：谐波辨识屏蔽信号经验模态分解二次模态筛选