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Journal of Forestry Research 2012年第2期23卷 191-196页

作者： lei cheng-liang JU Cun-yong CAI Ti-jiu J1NG Xia WEI Xiao-hua DI Xue-ying School of Forestry Northeast Forestry UniversityHarbin 150040P.R.China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054P.R.China Department of Earth and Environmental Science University of BritishColumbia(Okanagan)3333 University wayKelownaBritish Colum-biaCanadaV1V 1V7.

Boreal forests play an important role in global environment systems. Understanding boreal forest ecosystem structure and function requires accurate monitoring and estimating of forest canopy and biomass. We used partial least square regression （PLSR） models to relate forest parameters, i.e. canopy closure density and above ground tree biomass, to Landsat ETM＋ data. The established models were optimized according to the variable importance for projection （VIP） criterion and the bootstrap method, and their performance was compared using several statistical indices. All variables selected by the VIP criterion passed the bootstrap test （p〈0.05）. The simplified models without insignificant variables （VIP 〈1） performed as well as the full model but with less computation time. The relative root mean square error （RMSE%） was 29% for canopy closure density, and 58% for above ground tree biomass. We conclude that PLSR can be an effective method for estimating canopy closure density and above ground biomass.

关键词： above-ground tree biomass bootstrap method canopy clo- sure density partial least square regression (PLSR) VIP criterion

Joint Probabilistic Scheduling and Resource Allocation for Wireless Networked Control Systems

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 258-260页

作者： Meng Zheng lei Zhang Wei liang IEEE the State Key Laboratory of Robotics and the Key Laboratory of Networked Control Systems Shenyang Institute of Automation Chinese Academy of Sciences the University of Chinese Academy of Sciences

Dear Editor,This letter presents a joint probabilistic scheduling and resource allocation method(PSRA) for 5G-based wireless networked control systems(WNCSs). As a control-aware optimization method, PSRA minimizes the linear quadratic Gaussian(LQG) control cost of WNCSs by optimizing the activation probability of subsystems, the number of uplink repetitions, and the durations of uplink and downlink phases. Simulation results show that PSRA achieves smaller LQG control costs than existing works.

关键词：

Force and impulse multi-sensor based on flexible gate dielectric field effect transistor

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 214-220页

作者： Chao Tan Junling Lü Chunchi Zhang Dong liang lei Yang Zegao Wang College of Materials Science and Engineering Sichuan UniversityChengdu 610065China The 54th Research Institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

Nowadays,force sensors play an important role in industrial production,electronic information,medical health,and many other ***-dimensional material-based filed effect transistor(2D-FET)sensors are competitive with nano-level size,lower power consumption,and accurate ***,few of them has the capability of impulse detection which is a path function,expressing the cumulative effect of the force on the particle over a period of *** we fabricated the flexible polymethyl methacrylate(PMMA)gate dielectric MoS_(2)-FET for force and impulse sensor *** systematically investigated the responses of the sensor to constant force and varying forces,and achieved the conversion factors of the drain current signals(I_(ds))to the detected impulse(I).The applied force was detected and recorded by I_(ds)with a low power consumption of~30 *** sensitivity of the device can reach~8000%and the 4×1 sensor array is able to detect and locate the normal force applied on ***,there was almost no performance loss for the device as left in the air for two months.

关键词： flexible gate dielectric transistor force sensor impulse sensor force sensor array

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土压平衡顶管变形破损修复仿真研究

计算机仿真 2017年第10期34卷 237-240,452页

作者：许有俊程磊梁玮真张平内蒙古科技大学土木工程学院内蒙古包头014010 河北大学土木工程学院河北保定071002

对土压平衡顶管的变形破损进行修复,能够有效地保证土压平衡顶管工程施工质量。对顶管变形破损的修复,需要提取顶管变形破损工作面图像特征点,组建破损变换矩阵,完成对土压平衡顶管的变形破损的修复。传统方法先对破损工作面特征进行匹... 详细信息

对土压平衡顶管的变形破损进行修复,能够有效地保证土压平衡顶管工程施工质量。对顶管变形破损的修复,需要提取顶管变形破损工作面图像特征点,组建破损变换矩阵,完成对土压平衡顶管的变形破损的修复。传统方法先对破损工作面特征进行匹配,提取破损工作面三维基本特征体素,但忽略了组建破损变换矩阵,导致修复精度偏低。提出基于Retinex的土压平衡顶管变形破损工作面的三维修复方法。上述方法先用因子分解方法得到顶管变形破损射影空间下相机投影矩阵和物点坐标,依据光束法平差技术对所有参数进行求精,提取顶管变形破损工作面图像特征点,组建顶管变形破损工作面图像变换矩阵实现拼接,最后利用小波变换多分辨率融合理论进一步对顶管变形破损工作面图像融合处理,由此完成土压平衡顶管变形破损工作面三维修复。实验结果表明,所提方法具有较好的鲁棒性,且修复精度较高。

关键词：土压平衡顶管变形破损修复

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混合动力系统用发动机冷起动排放

上海交通大学学报 2010年第10期44卷 1352-1355页

作者：王存磊殷承良于海生上海交通大学汽车电子控制技术国家工程实验室上海200240

通过分析发动机起动点火、喷油及进气量控制策略,确定了发动机冷起动过程中影响HC和NOx排放的关键参数为:拖转转速、起始喷油转速和点火推迟.研究表明:较高的拖转转速可以减少发动机起动所需的燃油量、改善燃油雾化质量、促进完全燃烧... 详细信息

通过分析发动机起动点火、喷油及进气量控制策略,确定了发动机冷起动过程中影响HC和NOx排放的关键参数为:拖转转速、起始喷油转速和点火推迟.研究表明:较高的拖转转速可以减少发动机起动所需的燃油量、改善燃油雾化质量、促进完全燃烧、降低HC排放;而过高的拖转转速则会恶化NOx排放;推迟点火可以有效地加速催化器起燃、显著地降低排放,若点火太迟只能有限加速催化器起燃,而且会增加油耗、使燃烧不稳定、增加失火,HC及NOx排放同时恶化.通过研究排放规律,选定了合适的冷起动参数,为今后精确排放标定奠定了基础.

关键词：混合动力系统发动机冷起动排放标定

A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： Xiao liang Xingping Quan Xiaorui Geng Yujing Huang Yonghua Zhao lei Xi Zhen Yuan Ping Wang Bin Liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

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重力勘探法在侵入岩体导矿构造上的分析应用

地球物理学进展 2012年第4期27卷 1679-1686页

作者：姚绍萍徐荣华晏俊灵雷良城江西省地质调查研究院南昌330030

在全国矿产资源潜力评价工作中,如何在与侵入岩体成矿相关矿种中提取与导矿相关的导矿岩体与构造,提高重力资料的研究程度和应用水平,使重力勘探在研究多金属矿产的物质来源,示矿信息等诸方面起到有效的作用.本文从江西省德兴-婺源地区... 详细信息

在全国矿产资源潜力评价工作中,如何在与侵入岩体成矿相关矿种中提取与导矿相关的导矿岩体与构造,提高重力资料的研究程度和应用水平,使重力勘探在研究多金属矿产的物质来源,示矿信息等诸方面起到有效的作用.本文从江西省德兴-婺源地区的15万重力测量资料研究中,通过使用RGIS2010重磁电数据处理软件对15万重力测量数据进行趋势分析,求取四阶趋势剩余场,通过对重力剩余场与地质构造,岩体的重力场体现,使用重力归一化梯度辅助反演解释岩体的空间形态特征,为金属矿产预测提供矿源物质提供来源通道和预测岩体深度提供依据.

关键词：矿产资源潜力评价侵入岩趋势分析重力归一化梯度反演 RGIS2010

离子缔合与中性络合协萃取体系(二)——TPAsN—MIBK对硝酸氧铀的协同萃取

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四川大学学报(自然科学版) 1966年第1期 65-76页

作者：祝霖陈绍金雷良臣

文献研究了TBAN与MIBK对UO2（NO3）2的萃取行为,证明它属于BC类协萃体系,并且提出了这类体系萃取机理的研究方法。但是到目前为止,对BC类协萃体系研究还很少,我们认为为了探明这类协萃体系的规律,一方面应当研究更多的体系,以便总结出... 详细信息

文献研究了TBAN与MIBK对UO2（NO3）2的萃取行为,证明它属于BC类协萃体系,并且提出了这类体系萃取机理的研究方法。但是到目前为止,对BC类协萃体系研究还很少,我们认为为了探明这类协萃体系的规律,一方面应当研究更多的体系,以便总结出共同的规律,另一方面应当继续选择典型的体系研究萃取机构,并进一步探索新的研究方法。本文继文献之后,研究了离子萃取剂硝酸四苯（钅申）（简称TPAsN）与MIBK对硝酸铀酰的萃取机构。

关键词： MIBK 甲基异丁基酮 TPAsN 萃取体系协同萃取溶剂萃取硝酸氮化合物

Human-induced pluripotent stem cell-derived neural stem cell exosomes improve blood-brain barrier function after intracerebral hemorrhage by activating astrocytes via PI3K/AKT/MCP-1 axis

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Neural Regeneration Research 2025年第2期20卷 518-532页

作者： Conglin Wang Fangyuan cheng Zhaoli Han Bo Yan Pan Liao Zhenyu Yin Xintong Ge Dai Li Rongrong Zhong Qiang Liu Fanglian Chen Ping lei Department of Geriatrics Tianjin Medical University General HospitalTianjinChina School of Medicine Nankai UniversityTianjinChina Tianjin Neurological Institute TianjinChina

Cerebral edema caused by blood-brain barrier injury after intracerebral hemorrhage is an important factor leading to poor ***-induced pluripotent stem cell-derived neural stem cell exosomes(hiPSC-NSC-Exos)have shown potential for brain injury repair in central nervous system *** this study,we explored the impact of hiPSC-NSC-Exos on blood-brain barrier preservation and the underlying *** results indicated that intranasal delivery of hiPSC-NSC-Exos mitigated neurological deficits,enhanced blood-brain barrier integrity,and reduced leukocyte infiltration in a mouse model of intracerebral ***,hiPSC-NSC-Exos decreased immune cell infiltration,activated astrocytes,and decreased the secretion of inflammatory cytokines like monocyte chemoattractant protein-1,macrophage inflammatory protein-1α,and tumor necrosis factor-αpost-intracerebral hemorrhage,thereby improving the inflammatory *** sequencing indicated that hiPSC-NSC-Exo activated the PI3K/AKT signaling pathway in astrocytes and decreased monocyte chemoattractant protein-1 secretion,thereby improving blood-brain barrier *** with the PI3K/AKT inhibitor LY294002 or the monocyte chemoattractant protein-1 neutralizing agent C1142 abolished these *** summary,our findings suggest that hiPSC-NSC-Exos maintains blood-brain barrier integrity,in part by downregulating monocyte chemoattractant protein-1 secretion through activation of the PI3K/AKT signaling pathway in astrocytes.

关键词： AKT astrocyte blood-brain barrier cerebral edema exosomes human-induced pluripotent stem cells intracerebral hemorrhage neural stem cells neuroinflammation PI3K

LISS系统对股骨远端骨折患者炎性指标及短缩程度的影响

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中国伤残医学 2018年第11期26卷 9-11页

作者：雷志雄程良才叶枪广东省茂名市电白区人民医院骨科广东茂名525400

目的：探究微创内固定系统（LISS）时股骨远端骨折患者的炎性指标及短缩程度影响。方法：将60例股骨远端骨折患者分为对照组和观察组，各30例，对照组予传统股骨髁钢板内固定术，观察组采用LISS系统，对比分析2组患者手术情况、炎性指... 详细信息

目的：探究微创内固定系统（LISS）时股骨远端骨折患者的炎性指标及短缩程度影响。方法：将60例股骨远端骨折患者分为对照组和观察组，各30例，对照组予传统股骨髁钢板内固定术，观察组采用LISS系统，对比分析2组患者手术情况、炎性指标、关节恢复情况以及短缩程度。结果：观察组患者手术情况及术后负重时间明显优于对照组（P=0．000）。术后观察组白细胞介素1、肾上腺素、去甲肾上腺素、促肾上腺皮质激素水平以及Harris评分显著优于对照组（P=0．000）。观察组治疗效果优良率达83．33％，显著高于对照组（60．00％），P=0．000。2组患者术后3个月短缩程度比较差异无统计学意义（P=0．659）。结论：LISS系统能有效减轻术后炎症反应，缩短患者术后恢复时间，促进骨折愈合，改善关节功能活动，但在纠正骨折短缩程度方面与传统钢板内固定术无明显差异。

关键词： LISS系统股骨远端骨折炎性指标短缩程度