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Fungal spore record of pastoralism on the NE Qinghai-Tibetan Plateau since the middle Holocene

Science China Earth Sciences 2021年第8期64卷 1318-1331页

作者： haicheng wei Chongyi E Ronglei DUAN Jing ZHANG Yongjuan SUN Guangliang HOU Jingyi GAO Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt LakesChinese Academy of SciencesXining 810008China Qinghai Provincial Key Laboratory of Physical Geography and Environmental Processes School of Geographic ScienceQinghai Normal UniversityXining 810008China Academy of Plateau Science and Sustainability Qinghai Normal UniversityXining 810008China

Pastoralism is considered a crucial factor in the eventual year-round occupation of high-altitude regions(>3000 m asl)of the Qinghai-Tibetan Plateau,and the northeastern Qinghai-Tibetan Plateau(NE-QTP)was an important corridor for early human *** analyzed fossil fungal spore records for the last 8500 years from a high resolution aeolian section at Langgeri(LGR)on the ***-two fungal spore types were identified in the LGR section,including seven coprophilous *** combined analysis of coprophilous fungal spores,Cyperaceae,Artemisia,and Hippophae pollen,and the charcoal>50µm fraction to explore the timing and controls of pastoralism on the NE-QTP since the middle *** commenced at LGR shortly before ca.5.5 ka and gradually increased between ca.5.5–3.5 ka,but markedly intensified after ca.2.2 ka,with three periods of growth at ca.2.1–1.9,1.4–1.2,and 0.6–0 ka,and a decline at ca.1.1–0.6 *** timing of changes in pastoral activity on the NE-QTP based on the coprophilous fungal spore record is supported by regional archeology and historical *** and political developments,rather than climate change,played key roles in the long-term fluctuations of regional pastoralism on the NE-QTP in the late Holocene.

关键词： Coprophilous fungal spores Pastoralism Qinghai Lake basin Holocene Qinghai-Tibetan Plateau

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Optical and scintillation properties of Bi_4Si_3O_(12):RE(RE=Eu^(3+), Sm^(3+),Ho^(3+), Tb^(3+))single crystals

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Journal of Rare Earths 2019年第3期37卷 260-264页

作者： Xuefeng Xiao Jiayue Xu haicheng wei Yaoqing Chu Bobo Yang Xuefeng Zhang Key Laboratory of Physics and Photoelectric Information Functional Materials Sciences and Technology North Minzu University College of Electric and Information Engineering North Minzu University School of Materials Science and Engineering Tongji University School of Materials Science and Engineering Shanghai Institute of Technology Ningxia Ju Jing Yuan Crystal Technology Company Limited

Bi_4 Si_3 O_(12):RE(BSO:RE, RE = Eu^(3+), Sm^(3+), Ho^(3+), Tb^(3+)) crystals were grown by the modified vertical Bridgeman method, and doping effects on scintillation properties were investigated. Under γ-ray irradiation, the light yield of BSO doped with small doses of Eu^(3+) increases slightly, and the energy resolution improves significantly compared to pure BSO, therefore the ability of distinguishing between particles will be improved for BSO crystals with a small amount of Eu^(3+) dopant. The results show that a small amount of Eu^(3+) doping can sensitize the Bi^(3+) ions. The sensitization effect enables the reduction of intrinsic defects, and thus improves the scintillation properties. However, the relative light yield of BSO:Tb(1.0 mol%) crystal is 4.3%, which is smaller than 5.0% of pure BSO. The improved light yield and energy resolution in the BSO:Eu and BSO:Sm crystals are considered an impressive achievement in the optimization of this scintillator which is already suitable for applications such as dual-readout calorimeters and homogeneous hadron calorimeters.

关键词： BSO crystal Vertical Bridgeman method Scintillation characteristics Relative light yield Rare earths

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New Method to Nonquadratic Tracking Control for Continuous-time T-S Fuzzy Systems 36

New Method to Nonquadratic Tracking Control for Continuous-t...

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第36届中国控制会议

作者： PAN Juntao LIU Fang wei haicheng ZHANG Bai School of Electrical and Information Engineering Beifang University of Nationalities

ISBN: (纸本)9781538629185

This paper is concerned with the tracking control problem for continuous-time Takagi-Sugeno(T-S) fuzzy *** is focused on the design of a tracking controller attenuating the tracking error as small as possible in the H performance *** for designing tracking controller are established based on a novel nonquadratic Lyapunov function whose integral structure allows circumventing the well known problem of handing time-derivatives of membership functions(MFs).It is shown that conditions for the solvability of the tracking controller design given here are written in the form of linear matrix inequality(LMI) which can be efficiently solved by convex optimization *** simulation example is given to demonstrate the validity of the proposed approach.

关键词： Nonquadratic Lyapunov function Continuous-time T-S fuzzy systems Tracking control

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Characterization of the retinal vasculature in fundus photos using the PanOptic iExaminer system

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Eye and Vision 2020年第2期7卷 444-453页

作者： Huiling Hu haicheng wei Mingxia Xiao Liqiong Jiang Huijuan Wang Hong Jiang Tatjana Rundek Jianhua Wang Shenzhen Key Laboratory of Ophthalmology Shenzhen Eye HospitalJinan UniversityShenzhenChina Department of Ophthalmology Bascom Palmer Eye InstituteUniversity of Miami Miller School of Medicine1638 NW 10th AvenueMcKnight Building-Room 202AMiamiFL 33136USA Department of Electrical and Computer Engineering Florida International UniversityMiamiFLUSA School of Electrical and Information Engineering North Minzu UniversityYinchuanNingxiaChina Eye hospital China Academy of Chinese Medical SciencesBeijingChina Department of Neurology University of Miami Miller School of MedicineMiamiFLUSA

Background:The goal was to characterize retinal vasculature by quantitative analysis of arteriole-to-venule(A/V)ratio and vessel density in fundus photos taken with the PanOptic iExaminer ***:The PanOptic ophthalmoscope equipped with a smartphone was used to acquire fundus photos centered on the optic nerve *** fundus photos of a total of 19 eyes from 10 subjects were *** vessels were analyzed to obtain the A/V *** addition,the vessel tree was extracted using deep learning U-NET,and vessel density was processed by the percentage of pixels within vessels over the entire ***:All images were successfully processed for the A/V ratio and vessel *** was no significant difference of averaged A/V ratio between the first(0.77±0.09)and second(0.77±0.10)measurements(P=0.53).There was no significant difference of averaged vessel density(%)between the first(6.11±1.39)and second(6.12±1.40)measurements(P=0.85).Conclusions:Quantitative analysis of the retinal vasculature was feasible in fundus photos taken using the PanOptic *** device appears to provide sufficient image quality for analyzing A/V ratio and vessel density with the benefit of portability,easy data transferring,and low cost of the device,which could be used for pre-clinical screening of systemic,cerebral and ocular diseases.

关键词： Smartphone ophthalmoscope Image analysis Deep learning Arteriovenous ratio Vessel density Retina

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Evaluation of boron isotopes in halite as an indicator of the salinity of Qarhan paleolake water in the eastern Qaidam Basin, western China

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Geoscience Frontiers 2019年第1期10卷 253-262页

作者： Yongsheng Du Qishun Fan Donglin Gao haicheng wei Fashou Shan Binkai Li Xiangru Zhang Qin Yuan Zhanjie Qin Qianhui Ren Xueming Teng Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources Qinghai Institute of Salt Lakes Chinese Academy of Sciences Key Laboratory of Salt Lake Geology and Environment of Qinghai Province University of Chinese Academy of Sciences Tianjin Center China Geological Survey

In this study, nineteen brine samples from the Qarhan Salt Lake(QSL) in western China were collected and analyzed for boron(B) and chlorine(Cl) concentrations, total dissolved solids(TDS), pH values and stable B isotopic compositions. The B concentrations and δ^(11) B values of brines in the QSL range from 51.6 mg/L to138.4 mg/L, and from +9.32& to +13.08&, respectively. By comparison of B concentrations and TDS of brines in QSL with evaporation paths of brackish water, we found that B enrichment of brines primarily results from strong evaporation and concentration of Qarhan lake water. Combining with comparisons of B concentrations, TDS, p H values and δ^(11) B values of brines, previously elemental ratios(K/Cl, Mg/Cl, Ca/Cl, B/Cl) and δ^(11) B values of halite from a sediment core(ISL1 A), we observe good correlations between B concentrations and TDS, TDS and pH values, pH and δ^(11) B values of brines, which demonstrate that higher B concentrations and more positive δ^(11) B values of halite indicate higher salinity of the Qarhan paleolake water as well as drier paleoclimatic conditions. Based on this interpretation of the δ^(11) B values of halite in core ISL1 A, higher salinity of the Qarhan paleolake occurred during two intervals, around 46-34 ka and26-9 ka, which are almost coincident with the upper and lower halite-dominated salt layers in core ISL1 A,drier climate phases documented from the δ^(18) O record of carbonate in core ISL1 A and the paleomoisture record in monsoonal central Asia, and a higher solar insolation at 30°N. These results demonstrate that the δ^(11) B values of halite in the arid Qaidam Basin could be regarded as a new proxy for reconstructing the salinity record of paleolake water as well as paleoclimate conditions.

关键词： B isotope compositions Brine Chemical concentrations Qarhan salt lake Western China Salinity of paleolake water

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Late Holocene hydroclimatic variations at Lake Hurleg， Northeastern Tibet Plateau

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Journal of Earth Science 2024年

作者： Aiying Cheng Junqing Yu Yun Li haicheng wei Chunliang Gao Lisha Zhang Key Laboratory of Green and High-end Utilization of Salt Lake Resources， Qinghai Institute of Salt Lakes， Chinese Academy of Sciences Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Haixi Prefecture Salt Lake Administration of Qinghai Province

High-resolution， continuous late Holocene lacustrine records are scarce in the Qaidam Basin， but is of especially important for our understanding the future climate variability in the western China. Here， we use grain size， element content and XRD-identified data from the Lake Hurleg in the eastern Qaidam Basin to present the late Holocene climate variability， which have been temporally constrained using210Pb-，137Cs- and AMS14C dating. Our records demonstrate that decreased precipitation climate occurred at ～800-1000 yr and ～1300-1800 yr intervals， and increased precipitation occurred at ～354-800 yr，～1000-1300 yr and ～1800 yr to the present. The results show that the Qaidam Basin has undergone a process of warming and humidification since the Industrial Revolution， which is consistent with the meteorological records. The climate in the northeastern Qaidam Basin is dominated by the Asian monsoon.

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A 94-ka Pollen Record of Vegetation Change in Qaidam Basin,Northeastern Qinghai-Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 31-33页

作者： wei haicheng FAN Qishun ZHAO Yan MA Haizhou AN Fuyuan' YUAN Qin CAS Key Laboratory of Salt Lake Resources and Chemistry Qinghai Institute of Salt Lakes Chinese Academy of Sciences Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences

1 Introduction The northeastern Qinghai-Tibetan Plateau(NE QTP),located at a triple junction of influences of the Asian summer monsoon,westerly jet stream and Siberian high,is of considerable significance with regard ... 详细信息

关键词： Pollen record Climate change Qaidam Basin Late Pleistocene Qinghai-Tibetan Plateau(QTP)

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Distribution characteristics and indicative significance of grain size and elemental content in surface-sediments of Qinghai Lake， Northeastern Tibetan Plateau

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Journal of Earth Science 2024年

作者： Yuqi Cheng haicheng wei Ronglei Duan Shun Wang Zhixiang Wang Hongyu Li Fangming Zeng Yilin Hou Hongpan Xue Key Laboratory of Green and High-end Utilization of Salt Lake Resources， Qinghai Institute of Salt Lakes， Chinese Academy of Sciences Qinghai Provincial Key Laboratory of Geology and Environment of Salt Lakes Qinghai Institute of Salt Lakes， Chinese Academy of Sciences University of Chinese Academy of Sciences

Qinghai Lake in the northeastern Qinghai-Tibet Plateau (QTP)， being sensitive to paleoclimate change and anthropogenic activities， has attracted much attention from paleoenvironmental researchers. Grain size and elemental content in lake sediments are indispensable proxies for reconstructing paleoclimate and paleoenvironment. However， limited research on grain size and elemental content of surface-sediments in Qinghai Lake complicates decoding the information from lacustrine sedimentary strata. In this study， 55 surface-sediment samples were collected for grain size and elemental content analysis， combined with grain size end-member modeling algorithm (EMMA)， correlation (CA) and principal component (PCA) analysis to explore the controlling mechanisms and their environmental indications. Our results show that the hydrodynamic condition controls the distribution of surface-sediments in Qinghai Lake: exhibiting a belt-like pattern of sand-silt-clay， the clockwise circulation in the northwestern and southwestern lake transports sand to the two primary sedimentary centers. Three primary components representing different transport/depositional processes were separated: ‘lacustro-aeolian’， ‘fluvio-aeolian’ and river-transported bedload. Grain size controls the elemental content， particularly in terrestrial particles. Nitrogen (N) and phosphorus (P)， mainly derived from endogenous organic matter (OM)， tend to be absorbed by finer particles. The hydrodynamic conditions and anthropogenic activities also influence their spatial distribution. The chemical weathering index (CIA)， indicating a cold and dry climate， is highly related to grain size. This research provides crucial modern process references for accurately interpreting grain size and element records in sediment cores from Qinghai Lake.

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基于ZigBee的远程环境监测人机交互系统设计

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现代电子技术 2017年第18期40卷 156-160页

作者：魏鑫韦海成北方民族大学电气信息工程学院宁夏银川750021

针对传统的室内环境监测系统传输距离短、采集到的数据形式单一且需要进行人工处理的缺陷,设计并实现了一个基于ZigBee的远程环境监测人机交互系统。系统采用模块化的设计方案,整个系统由数据采集终端、ZigBee无线传感网和LabVIEW人机... 详细信息

针对传统的室内环境监测系统传输距离短、采集到的数据形式单一且需要进行人工处理的缺陷,设计并实现了一个基于ZigBee的远程环境监测人机交互系统。系统采用模块化的设计方案,整个系统由数据采集终端、ZigBee无线传感网和LabVIEW人机交互界面三部分组成。数据采集终端以STM32微控制器为主控芯片,连接各传感器采集环境数据。数据采集终端通过ZigBee无线传感网和USB转串口模块与上位机通信,上位机通过LabVIEW人机交互界面将数据采集终端测得的环境数据以仪表和折线图的形式显示出来。实验表明,系统稳定性和可扩展性较强、传输距离较远,且无需人工处理即可将每天测得的环境数据以折线图形式直观展现出来,具有一定的科研意义和实用价值。

关键词： ZigBee无线传感网 LabVIEW人机交互界面环境监测 STM32

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ECG信号自适应贝叶斯小波去噪算法研究

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现代电子技术 2019年第5期42卷 61-65页

作者：赵静韦海成宁夏大学信息工程学院宁夏银川750021 北方民族大学电气信息工程学院宁夏银川750021

ECG信号是当前移动健康监护的一个常规生物电信号,在该信号采集过程中,常规的硬件放大电路会引入噪声,影响了信号的特征分析。针对ECG信号采集中的噪声消除问题,提出一种基于贝叶斯小波分析的去噪算法。首先对ECG信号进行小波分解,再通... 详细信息

ECG信号是当前移动健康监护的一个常规生物电信号,在该信号采集过程中,常规的硬件放大电路会引入噪声,影响了信号的特征分析。针对ECG信号采集中的噪声消除问题,提出一种基于贝叶斯小波分析的去噪算法。首先对ECG信号进行小波分解,再通过贝叶斯算法重新计算最佳小波系数阈值和加权系数,最终实现ECG信号的去噪和重构。实验结果表明:该算法能够较好地消除ECG信号的噪声,在保留较多信号细节的同时减少了信号失真。相对于小波软阈值和硬阈值算法,该算法的MSE为0.287 1,PSNR值为53.550 7,明显优于前者,具有较高的实际使用价值。

关键词：贝叶斯小波分析心电图信号去噪信号重构小波阈值

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