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Risk assessment of agricultural green water security in Northeast China under climate change

Science China Earth Sciences 2024年第7期67卷 2178-2194页

作者： Jingxuan SUN Guangxin ZHANG yanfeng wu Liwen CHEN Peng QI Boting HU Yijun XU Northeast Institute of Geography and Agroecology.Chinese Academy of Sciences Changchun 130102China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China School of Renewable Natural Resources Louisiana State University Agricultural Center227 Highland RoadBaton RougeLA 70803USA

Northeast China is an important base for grain production,dominated by rain-fed agriculture that relies on green ***,in the context of global climate change,rising regional temperatures,changing precipitation patterns,and increasing drought frequency pose threats and challenges to agricultural green water *** study provides a detailed assessment of the spatiotemporal characteristics and development trends of green water security risks in the Northeast region under the base period(2001-2020)and the future(2031-2090)climate change scenarios(SSP245 and SSP585)using the green water scarcity(GWS)index based on raster-scale crop spatial distribution data,Delta downscaling bias-corrected ERA5 data,and CMIP6 multimodal *** the base period,the green water risk-free zone for dry crops is mainly distributed in the center and east of the Northeast region(72.4% of the total area),the low-risk zone is primarily located in the center(14.0%),and the medium-risk(8.3%)and high-risk(5.3%)zones are mostly in the *** SSP245 and SSP585 future climate change scenarios,the green water security risk shows an overall expansion from the west to the center and east,with the low-risk zone increasing to 21.6% and 23.8%,the medium-risk zone increasing to 16.0% and 17.9%,and the high-risk zone increasing to 6.9% and 6.8%,*** dry crops with GWS greater than 0.1 as in need of irrigation,the irrigated area increases from 27.6%(base period)to 44.5%(SSP245)and 48.6%(SSP585),with corresponding increases in irrigation water requirement(IWR)of 4.64 and 5.92 billion m~3,respectively,which further exacerbates conflicts between supply and demand of agricultural water *** response to agricultural green water security risks,coping strategies such as evapotranspiration(ET)-based water resource management for dry crops and deficit irrigation are *** results of this study can provide scientific basis and decision support for the development

关键词： Climate change Food security Green water security risk Irrigation water requirement Green water scarcity

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Machine Allocation in Semiconductor Wafer Fabrication Systems:A Simulation-Based Approach

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Journal of Systems Science and Systems Engineering 2023年第3期32卷 372-390页

作者： yanfeng wu Sihua Chen School of Finance Jjiangxi University of Finance and EconomicsNanchang 330013China School of Information Management Jiangxi University of Finance and EconomicsNanchang 330032China

The problem of maximizing the throughput of Semiconductor Wafer Fabrication Systems is *** model the fabrication systems as a Stochastic Timed Automata and design a discrete-event simulation *** simulation scheme is explicit,fast and achieves high fidelity which captures the feature of reentrant process flow and is flexible to accommodate diversified wafer lot scheduling policies.A series of Marginal Machine Allocation Algorithms are proposed to sequentially allocate *** experiments suggest the designed methods are efficient to find good allocation solutions.

关键词： Semiconductor wafer fabrication system machine allocation discrete-event simulation marginal machine allocation

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Quantitative assessment on basin-scale hydrological services of wetlands

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Science China Earth Sciences 2020年第2期63卷 279-291页

作者： yanfeng wu Guangxin ZHANG Alain NROUSSEAU Northeast Institute of Geography and Agroecology Chinese Academy of SciencesChangchun 130102China University of Chinese Academy of Sciences Beijing 100049China INRS-ETE/Institut National de la Recherche Scientifique-Eau Terre Environnement Quebec G1K 9A9Canada

Despite recognizing the importance of hydrological function of wetlands, basin-scale wetlands services have rarely been investigated. The PHYSITEL/HYDROTEL modelling platform was used to quantitatively assess the impact of wetlands on quickflow and baseflow with paired simulation scenarios in Duobukuli River Basin, namely with wetlands and without *** results showed that wetlands exert significant impact on basin hydrological processes by decreasing streamflow and altering streamflow regime(magnitude, frequency, duration and time of flow events). The intensity(significant or not) of wetlands influences on quickflow had daily, monthly and annual variation. Wetlands significantly attenuated quickflow during flood season while slightly support daily, monthly and annual baseflow. The average quickflow attenuation and baseflow support of wetlands were 5.89% and 0.83%, respectively. Although the intensity and effect(mitigation or augment) of wetlands on streamflow temporally varied at daily, monthly, seasonal and annual scales, wetland overall mitigated quickflow and augment baseflow in Duobukuli River Basin. Our results could provide insights for future decision-making for rehabilitation and conservation of wetlands as well as integrated basin water resources management.

关键词： Wetlands modules Hydrological processes simulation Baseflow support Quickflow mitigation Hydrological function

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间充质干细胞来源的外泌体治疗放射性肠炎的疗效与安全性

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中国肿瘤生物治疗杂志 2024年第4期31卷 359-364页

作者：何晓波虞淦军高晓刚吴艳峰海军军医大学基础医学院免疫学教研室暨免疫与炎症全国重点实验室上海200433 海军军医大学第一附属医院器官移植科上海200433

目的:探讨间充质干细胞来源的外泌体(MSC-Exo)对人结肠癌CT26细胞体外增殖、迁移的影响及对放射性肠炎(RE)荷瘤小鼠模型的治疗效果及其安全性。方法:利用商品化含MSC-Exo的液体敷料产品(MSC-Exo产品),通过纳米颗粒追踪分析、透射电镜、W... 详细信息

目的:探讨间充质干细胞来源的外泌体(MSC-Exo)对人结肠癌CT26细胞体外增殖、迁移的影响及对放射性肠炎(RE)荷瘤小鼠模型的治疗效果及其安全性。方法:利用商品化含MSC-Exo的液体敷料产品(MSC-Exo产品),通过纳米颗粒追踪分析、透射电镜、WB法对其中的MSC-Exo进行鉴定。采用CCK-8法和Transwell小室法检测MSC-Exo产品对结肠癌CT26细胞增殖、迁移的影响。构建CT26细胞荷瘤小鼠模型,连续7 d分别给予400μL MSC-Exo产品、MSC培养基或生理盐水灌胃,评估MSC-Exo产品在体内对肿瘤生长和小鼠生存的影响。构建RE荷瘤小鼠模型,连续7 d分别给予400μL MSC-Exo产品、MSC培养基、生理盐水灌胃治疗,通过小肠组织H-E染色法评估MSC-Exo产品治疗RE的有效性与安全性。结果:纳米颗粒追踪分析、透射电镜、WB法的鉴定结果确证了商品化的液体敷料中含有MSC-Exo有效成分。体外研究表明,MSC-Exo产品成分不会促进结肠癌CT26细胞的增殖和迁移,具有安全性。体内研究结果发现,MSC-Exo产品的灌胃给药并不影响荷瘤小鼠的肿瘤生长和生存期,但RE荷瘤小鼠模型接受MSC-Exo产品灌胃治疗后,荷瘤小鼠血便、黏液便症状得到缓解,H-E染色结果显示小鼠肠壁组织的组织形态完整性相较于对照组有所改善,提示MSC-Exo产品对荷瘤小鼠的RE具有疗效,并且在致瘤性及肿瘤转移方面具有安全性。结论:商品化含MSC-Exo的液体敷料并不促进体外结肠癌细胞的增殖、迁移,对CT26细胞荷瘤小鼠肿瘤生长和生存期无明显影响,但对荷瘤小鼠模型的RE具有治疗作用,改善了肠道组织的损伤。

关键词：间充质干细胞外泌体肿瘤放射性肠炎

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基于声学的水下惯性导航系统校准技术研究

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传感器与微系统 2024年第5期43卷 35-38页

作者：吴艳峰鲍敬源韩云峰李超海军装备部北京100071 海装武汉局驻武汉地区第二军事代表室湖北武汉430064 哈尔滨工程大学黑龙江哈尔滨150001 中国船舶集团有限公司第710研究所湖北宜昌443000

随着海洋开发的进程推展,自主式水下潜航器(AUV)的导航技术也在日益进步。随着技术的探索,发现惯性导航的声学导航结合的导航模式才是未来的主要导航方向。因此,提出一种基于声学的水下惯性导航系统(INS)校准方法,其定位精度由惯导精度... 详细信息

随着海洋开发的进程推展,自主式水下潜航器(AUV)的导航技术也在日益进步。随着技术的探索,发现惯性导航的声学导航结合的导航模式才是未来的主要导航方向。因此,提出一种基于声学的水下惯性导航系统(INS)校准方法,其定位精度由惯导精度、安装偏差和声学定位精度综合决定。结果显示,在水下平台采用高精度光纤惯导并精确测量安装偏差的条件下,此方法能够获取不大于100 m的定位精度,能够很好地为水下平台提供导航系统修正。

关键词：惯性导航系统声学导航声学校准

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基于激光雷达的果园沟型测量平台设计与试验

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农机化研究 2024年第3期46卷 62-69,75页

作者：吴岩峰坎杂戚江涛周馨曌李亚萍石河子大学机械电气工程学院新疆石河子832000 农业部西北农业装备重点实验室新疆石河子832000

针对现有检测开沟质量效率低、精度差等问题,设计了一套由激光雷达、编码器、便携式计算机和支架等构成的非接触式果园开沟宽度深度监测平台,基于编码器获取测量平台前行方向位移,并与上位机软件形成整套采集系统,可快速获取果园沟型三... 详细信息

针对现有检测开沟质量效率低、精度差等问题,设计了一套由激光雷达、编码器、便携式计算机和支架等构成的非接触式果园开沟宽度深度监测平台,基于编码器获取测量平台前行方向位移,并与上位机软件形成整套采集系统,可快速获取果园沟型三维坐标。为了降低外部环境对点云数据处理的影响,采用直通滤波进行果园沟型的有效区域选取,借助MatLab获取其三维点云模型,实现对果园开沟沟形的重构与沟深、沟宽数据的监测。通过重构沟型参数与实测参数对比分析可知:两者宽度相关系数为0.83,均方根误差为0.008,相对误差为2.47%;深度相关系数为0.75,均方根误差为0.009,相对误差为2.76%。研究结果表明:重构沟型参数与实际沟型参数吻合度较高,可精确反映原有沟型形貌特征,为智慧农业果园开沟质量智能检测的构建提供了参考。

关键词：果园激光雷达沟型测量三维重建点云

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Infrared LSS-Target Detection Via Adaptive TCAIE-LGM Smoothing and Pixel-Based Background Subtraction

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Photonic Sensors 2019年第2期9卷 179-188页

作者： yanfeng wu Yanjie WANG Huiyuan LUO Boyang CHENG Haijiang SUN Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China University of Chinese Academy of Sciences Beijing 100049 China

Infrared small target detection is a significant and challenging topic for daily security. This paper proposes a novel model to detect LSS-target (low altitude, slow speed, and small target) under the complicated background. Firstly, the fundamental constituents of an infrared image including the complexity and entropy are calculated, which are invoked as adaptive control parameters of smoothness. Secondly, the adaptive L0 gradient minimization smoothing based on texture complexity and information entropy (TCAIE-LGM) is proposed in order to remove noises and suppress low-amplitude details in infrared image abstraction. Finally, difference of Gaussian (DoG) map is incorporated into the pixel-based adaptive segmentation (PBAS) background modeling algorithm, which can differ LSS-target from the sophisticated background. Experimental results demonstrate that the proposed novel model has a high detection rate and produces fewer false alarms, which outperforms most state-of-the-art methods.

关键词： Small target detection L0 smoothing texture complexity information entropy pixel-based adaptive segmentation

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Spatio-temporal patterns of drought in North Xinjiang, China, 1961–2012 based on meteorological drought index

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Journal of Arid Land 2015年第4期7卷 527-543页

作者： wu yanfeng Batur BAKE ZHANG Jusong Hamid RASULOV College of Grassland and Environmental Science Xinjiang Agricultural University College of Agronomy Xinjiang Agricultural University Faculty of Hydrometeorology Tajik Agrarian University

Drought, which is one of the most frequently occurring severe hazards with long time scales and cov- ering wide geographical areas, is a natural phenomenon resulting in significant economic losses in agriculture and industry. Drought is caused by an imbalance between the inputs of and the demand for water which is insufficient to meet the demands of human activities and the eco-environment. As a major arid and semi-arid area and an important agricultural region in Northwest China, North Xinjiang （NX） shows great vulnerability to drought. In this paper, the characteristics of inter-annual and seasonal drought were analyzed in terms of drought occurrence and drought coverage, by using the composite index of meteorological drought and the data of daily precipitation, air temperature, wind speed, relative humidity and sunshine duration from 38 meteorological stations during the period 1961-2012. Trend analysis, wavelet analysis and empirical orthogonal function were also applied to investigate change trend, period and regional characteristics, respectively. In NX, annual and seasonal drought occurrence and drought coverage all showed a decreasing trend that was most significant in winter （with rates of-0.26 month/10a and -15.46%, respectively）, and drought occurrence in spring and summer were more frequent than that in autumn and winter. Spatially, drought was severe in eastern regions but mild in western regions of NX. Annual and seasonal drought occurrence at 38 meteorological stations displayed decreasing trends and were most significant in ＂Shi- hezi-Urumqi-Changji＂, which can help to alleviate severe drought hazards for local agricultural production and improve human livelihood. NX can be approximately classified into three sub-regions （severe drought region, moder- ate drought region and mild drought region）, which were calculated from annual drought frequencies. The cross wavelet transform suggested that SOl （Southern Oscillation Index）, AOI （Arctic Oscillation I

关键词： drought spatio-temporal pattern drought indices North Xinjiang

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护患双方对老年住院患者跌倒预防的认知调查

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现代临床医学 2024年第1期50卷 51-55页

作者：杜晓李龙倜吴艳凤十堰市太和医院(湖北医药学院附属医院)护理部湖北十堰442000 十堰市人民医院(湖北医药学院附属医院)检验科湖北十堰442000

目的:调查护患双方对老年住院患者跌倒预防的认知现状,为老年住院患者跌倒预防干预措施的制定提供参考。方法:2022年9月1日至9月30日,选取十堰市1所三甲医院和4所二甲医院的700例老年住院患者及1480名护士为研究对象。采用住院患者跌倒... 详细信息

目的:调查护患双方对老年住院患者跌倒预防的认知现状,为老年住院患者跌倒预防干预措施的制定提供参考。方法:2022年9月1日至9月30日,选取十堰市1所三甲医院和4所二甲医院的700例老年住院患者及1480名护士为研究对象。采用住院患者跌倒预防之临床护士工作自评量表对护士进行问卷调查,采用住院老年病人参与跌倒预防知信行量表和跌倒效能量表对老年住院患者进行问卷调查。结果:护士对老年住院患者跌倒预防自评总分为(238.73±16.21)分;老年住院患者参与跌倒预防知信行总分为(110.09±20.79)分,跌倒效能总分为(86.64±16.23)分,老年住院患者参与跌倒预防知信行总分与跌倒效能总分呈正相关(r=0.258,P<0.05)。结论:护士对老年住院患者跌倒预防自评得分较高,但老年住院患者参与跌倒预防知信行水平较低,预防跌倒需要护士、患者及家属的共同努力。

关键词：跌倒老年住院患者护士知信行跌倒效能

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石膏基地面找平砂浆的制备

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新型建筑材料 2024年第8期51卷 147-150页

作者：汤青青赵伦伍艳峰东方雨虹砂粉科技集团有限公司北京101307

研究了石膏、水泥掺量以及减水剂、消泡剂、稳定剂、缓凝剂的种类和掺量对石膏基地面找平砂浆物理力学性能的影响。结果表明:当粉料组成为60%石膏+3%水泥+37%砂,消泡剂XP-1、稳定剂WD-2、减水剂PCE-2、缓凝剂HN-1掺量分别为粉料质量的0.... 详细信息

研究了石膏、水泥掺量以及减水剂、消泡剂、稳定剂、缓凝剂的种类和掺量对石膏基地面找平砂浆物理力学性能的影响。结果表明:当粉料组成为60%石膏+3%水泥+37%砂,消泡剂XP-1、稳定剂WD-2、减水剂PCE-2、缓凝剂HN-1掺量分别为粉料质量的0.06%、0.08%、0.25%、0.014%时制得的石膏基地面找平砂浆初始流动度为220 mm,1 d抗折、抗压强度分别为2.8、11.4 MPa,28 d抗折、抗压强度分别为7.9、21.8 MPa,14 d拉伸粘结强度为1.00 MPa,限制条件下的尺寸变化率为0.045 mm/m,符合JC/T 2326—2015《建筑找平砂浆》中C16的要求。

关键词：石膏基地面找平砂浆减水剂消泡剂稳定剂物理性能研究

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