检索结果-南通市图书馆

Digital surface model applied to unmanned aerial vehicle based photogrammetry to assess potential biotic or abiotic effects on grapevine canopies

引用

International Journal of Agricultural and Biological Engineering 2016年第6期9卷 119-130页

作者： Su Baofeng Xue Jinru xie chunyu Fang Yulin Song Yuyang Sigfredo Fuentes College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100China College of Enology Northwest A&F UniversityYangling 712100China Faculty of Veterinary and Agricultural Sciences University of MelbourneParkville 3010Australia

Accurate data acquisition and analysis to obtain crop canopy information are critical steps to understand plant growth dynamics and to assess the potential impacts of biotic or abiotic stresses on plant development.A versatile and easy to use monitoring system will allow researchers and growers to improve the follow-up management strategies within farms once potential problems have been *** study reviewed existing remote sensing platforms and relevant information applied to crops and specifically grapevines to equip a simple Unmanned Aerial Vehicle(UAV)using a visible high definition RGB *** objective of the proposed Unmanned Aerial System(UAS)was to implement a Digital Surface Model(DSM)in order to obtain accurate information about the affected or missing grapevines that can be attributed to potential biotic or abiotic stress *** analysis process started with a three-dimensional(3D)reconstruction from the RGB images collected from grapevines using the UAS and the Structure from Motion(SfM)technique to obtain the DSM applied on a per-plant ***,the DSM was expressed as greyscale images according to the halftone technique to finally extract the information of affected and missing grapevines using computer vision algorithms based on canopy cover measurement and *** validate the automated method proposed,each grapevine row was visually inspected within the study *** inspection was then compared to the digital assessment using the proposed UAS in order to validate calculations of affected and missing grapevines for the whole studied *** showed that the percentage of affected and missing grapevines was 9.5%and 7.3%,respectively from the area ***,for this specific study,the abiotic stress that affected the experimental vineyard(frost)impacted a total of 16.8%of *** study provided a new method for automatically surveying affected or missing grapevines in the field and an evaluation tool fo

关键词： remote sensing canopy cover viticultural management frost damage digital surface model

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Salt-assisted growth and ultrafast photocarrier dynamics of large-sized monolayer ReSe2

引用

Nano Research 2020年第3期13卷 667-675页

作者： Shaolong Jiang Jin Yang Yuping Shi Jing Zhao chunyu xie Liyun Zhao Jiatian Fu Pengfei Yang Yahuan Huan Qin xie Huachao Jiang Qing Zhang Xianlong Wang Fuhai Su Yanfeng Zhang Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei230031China University of Science and Technology of China Hefei230026China Center for Nanochemistry(CNC) Beijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871China

Owing to its anisotropic optical and electrical properties,rhenium diselenide(ReSe2)has garnered considerable attention recently as a candidate material for polarization-sensitive ***,the direct and controllable synthesis of large-sized ReSe2 with a uniform thickness is still a great ***,we have refined the synthesis method to obtain uniform monolayer ReSe2 flakes with a size of up to^106μm on sapphire via an ambient-pressure chemical vapor deposition technique using Na promoter from sodium ***,optical pump-probe spectroscopy revealed a fast switching from saturable absorption(SA)to absorption enhancement(AE)in subpicosecond time scale,followed by a slower decay induced by exciton ***,both AE and SA signals exhibited clear angular dependence with a periodicity of 180°,which reflected the dichroism in nonlinear absorption *** addition,the photocarrier dynamics including free-carrier transport and subpicosecond relaxation due to exciton formation or surface trapping was probed using time resolved terahertz *** believe that our study serves as a reference for atomically controlled synthesis of large-sized ReSe2 and provides useful insights on its optoelectronic properties for novel device applications.

关键词： ReSe2 chemical vapor deposition sodium chloride large size ultrafast photocarrier dynamics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defining stratigraphic oil and gas plays by modifying structural plays:A case study from the Xihu Sag,east China Sea Shelf Basin

引用

Energy Geoscience 2021年第1期2卷 41-51页

作者： Feng Ding chunyu xie Xinghai Zhou Cen Jiang Kun Li Lifeng Wan Pei Zhang Huawei Niu Shanghai Offshore Oil and Gas Exploration and Production Company SINOPECShanghai200120China

The study focuses on an area of relatively mature oil and gas exploration located in the western slope of the Xihu Sag,East China Sea Shelf *** stratigraphic oil and gas plays are introduced to replenish the shrinking prospect inventory in the *** reservoirs of these plays are traditional pay intervals of the Eocene Pinghu Formation and Baoshi Formation composed of tide-dominated delta front,tidal flat and delta front sand bar *** investigating conventional seismic data,seismic inversion volumes,and well log data,multiple tidal-influenced delta front channels,beach sand packages have been mapped out in different reservoir sand intervals of the Pinghu Formation and Baoshi *** recognize four types of stratigraphic terminations:channel flank pinch-outs,axial pinch-outs of sand-fills,channel mouth sand bar pinch-outs,and onlap pinch-outs for the Baoshi *** the depositional facies and relatively low sand-shale ratio of the reservoir formations favor the occurrence of stratigraphic *** closure mechanism of all these plays are similar to the traditional structure plays in the area:fault blocks or fault-bounded rollover anticlines,except that one or more closing faults are replaced by these stratigraphic *** small-sized closures should exist but the relatively large ones are centered around a major intra-slope rise,raising the exploration potential in this maturely explored *** new exploration drilling campaign has so far tested the play of delta front channel facies,with three out of four wells commercially *** play concepts open up a novel approach to identify new traps in the study area and many other rift basins with similar settings in eastern China.

关键词： East China Sea Xihu Sag Stratigraphic play Pinghu Formation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Application of chemical vapor-deposited monolayer ReSe2 in the electrocatalytic hydrogen evolution reaction

引用

Nano Research 2018年第4期11卷 1787-1797页

作者： Shaolong Jiang Zhepeng Zhang Na Zhang Yahuan Huan Yue Gong Mengxing Sun Jianping Shi chunyu xie Pengfei Yang Qiyi Fang He Li Lianming Tong Dan xie Lin Gu Porun Liu Yanfeng Zhang Department of Materials Science and Engineering College of Engineering Peking University Beijing 100871 China Center for Nanochemistry (CNC) Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100190 China Institute of Microelectronics Tsinghua National Laboratory for Information Science and Technology (TNList) Tsinghua University Beijing 100084 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China Centre for Clean Environment and Energy Griffith University Gold Coast 4222 Australia

Controlled synthesis of structurally anisotropic rhenium diselenide （ReSe2） with macroscopically uniform and strictly monolayer thickness as well as tunable domain shape/size is of great interest for electronics-, optoelectronics-, and electrocatalysis-related applications. Herein, we describe the controlled synthesis of uniform monolayer ReSe2 flakes with variable morphology （sunflower- or truncated-triangle-shaped） on SiO2/Si substrates using different ambient-pressure chemical vapor deposition （CVD） setups. The prepared polycrystalline ReSe2 flakes were transferred intact onto Au foil electrodes and tested for activity in the hydrogen evolution reaction （HER）. Interestingly, compared to the compact truncated-triangle-shaped ReSe2 flakes, their edge-abundant sunflower-shaped counterparts exhibited superior electrocatalytic HER activity, featuring a relatively low Tafel slope of - 76 mV/dec and an exchange current density of 10.5 μA/cm2. Thus, our work demonstrates that CVD-grown ReSe2 is a promising two- dimensional anisotropic material for applications in the electrocatalytic HER.

关键词： rhenium diselenide chemical vapor deposition(CVD) monolayer morphology control hydrogen evolution reaction (HER)

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Scalable salt-templated directed synthesis of high-quality MoS_(2) nanosheets powders towards energetic and environmental applications

引用

Nano Research 2020年第11期13卷 3098-3104页

作者： Lijie Zhu Pengfei Yang Yahuan Huan Shuangyuan Pan Zhaoqian Zhang Fangfang Cui Yuping Shi Shaolong Jiang chunyu xie Min Hong Jiatian Fu Jingyi Hu Yanfeng Zhang Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)have emerged as perfect platforms for developing applications in nano-electronics,catalysis,energy storage and environmental-related fields due to their superior ***,the low-cost,batch production of high-quality 2D TMDCs remains a huge challenge with the existing synthetic ***,we present a scalable chemical vapor deposition(CVD)approach for the batch production of high-quality MoS_(2) nanosheet powders,by using naturally abundant,water-soluble and recyclable NaCl crystal powders as *** high-quality MoS_(2) nanosheets powders are achieved by a facile water dissolution-filtration process,by virtue of the excellent dispersibility of the as-grown products in *** internal mechanism for the scalable synthesis strategy is *** applications of the MoS_(2) nanosheets powders are also demonstrated as catalysts or adsorbents in hydrogen evolution reaction(HER)and organic dyes adsorption,*** work should hereby pave ways for the mass production and application of powdery TMDCs in energetic and environmental related fields.

关键词： mass production salt-templated molybdenum disulfide chemical vapor deposition green transfer

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Space-confined growth of monolayer ReSe2 under a graphene layer on Au foils

引用

Nano Research 2019年第1期12卷 149-157页

作者： chunyu xie Shaolong Jiang Xiaolong Zou Yuanwei Sun Liyun Zhao Min Hong Shulin Chen Yahuan Huan Jianping Shi xiebo Zhou Zhepeng Zhang Pengfei Yang Yuping Shi Porun Liu Qing Zhang Peng Gao Yanfeng Zhang Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing 100871China Center far Nanochemistry(CNC) Beijing National Laboratory for Molecular SciencesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Tsinghua-Berkeley Shenzhen Institute(TBSI) Tsinghua UniversityShenzhen 518055China Electron Microscopy Laboratory School of PhysicsPeking UniversityBeijing 100871China International Center for Quantum Materials School of PhysicsPeking UniversityBeijing 100871China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China Centre for Clean Environment and Energy Griffith UniversityGold Coast 4222Australia Collaborative Innovation Center of Quantum Matter Beijing 100871China

Vertical heterostructures based on two-dimensional(2D)materials have attracted widespread interest for their numerous applications in electronic and optoelectronic ***,we report the direct construct!on of an abnormal graphene/ReSe2 stack on Au foils by a two-step chemical vapor deposition(CVD)*** the second growth stage,mono layer ReSe2 is found to prefere ntially evolve at the irUerface between the first-grown graphene layer and the Au *** unusual stacking behavior is unraveled by in-situ"cutting open"the upper graphene from the defects to expose the lower ReSe2 using scanning tunneling microscopy(STM).From combination of these results with density functional theory calculations,the domain boundaries and edge sites of graphene are proposed to be adsorption sites for Re and Se precursors,further facilitating the growth of ReSe2 at the van der Waals gap of graphene/*** work hereby offers an intriguing strategy for obtaining vertical 2D heterostructures featured with an ultra-clean interface and a designed stacking geometry.

关键词： graphene rhenium selenide chemical vapor deposition seanning tunneling microscopy two-dimensional(2D)heterostructure

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

基于贝塔分布的风电功率波动区间估计

引用

电力自动化设备 2014年第12期34卷 26-30,57页

作者：刘兴杰谢春雨华北电力大学电力工程系河北保定071003

风电的大规模并网使得风电功率的波动性对电网的影响越来越大,单一且确定的点预测往往不能满足电网风险分析和制定决策的需求。通过对风电功率预测误差分布特性的研究,提出利用预测功率区间分段方法与参数优化后的贝塔分布对具有偏态性... 详细信息

风电的大规模并网使得风电功率的波动性对电网的影响越来越大,单一且确定的点预测往往不能满足电网风险分析和制定决策的需求。通过对风电功率预测误差分布特性的研究,提出利用预测功率区间分段方法与参数优化后的贝塔分布对具有偏态性的功率预测误差频率分布进行拟合。同时根据估计区间最狭原则,实现一定置信水平下风电功率的波动区间估计。利用所建优化模型、正态分布模型和优化前的贝塔分布模型分别对某风电场历史数据进行分析,对比结果验证了优化贝塔分布模型能更有效地对功率预测区间进行估计。

关键词：风电功率预测预测误差概率分布贝塔分布区间估计

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

非对称信息下报童问题的质量激励研究

引用

管理评论 2018年第6期30卷 227-237页

作者：王谦谢春雨崔怡雯中国科学院大学经济与管理学院北京100190 中国科学院大数据挖掘与知识管理重点实验室北京100190

本文研究了非对称信息下"供应商-零售商"两级供应链的质量激励问题,根据零售商是否共享质量检测水平信息将问题情景分为单边道德风险和双边道德风险。每种情景下零售商分别根据内部或外部缺陷信息设计合同,共建立四个委托代理模型。经... 详细信息

本文研究了非对称信息下"供应商-零售商"两级供应链的质量激励问题,根据零售商是否共享质量检测水平信息将问题情景分为单边道德风险和双边道德风险。每种情景下零售商分别根据内部或外部缺陷信息设计合同,共建立四个委托代理模型。经分析可知,在单边道德风险情景中,两种质量激励合同都能实现对称信息下的最优决策;但在双边道德风险情景中,两种合同都不能实现该最优决策。最后通过数值实验,比较了双边道德风险下两种质量激励合同的效果。结果表明,零售商基于内部缺陷信息设计合同时,供应商的质量水平更高;当产品内外部缺陷成本之差较大时,零售商基于内部缺陷信息设计合同期望收益更高;反之,基于外部信息设计合同收益更高。

关键词：质量激励报童模型道德风险委托代理理论

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

行政事业单位内部控制建设的实践与探索

引用

深圳信息职业技术学院学报 2018年第3期16卷 93-97页

作者：谢春宇深圳市康宁医院广东深圳518020

近年来,随着改革的不断深入与社会经济的快速发展,行政事业单位越发重视内部管理,而在当前国家严厉惩治腐败的环境下,行政事业单位的内部控制问题显得尤为突出。因此,行政事业单位各级管理者要提高重视程度,充分认识当前内部控制制度建... 详细信息

近年来,随着改革的不断深入与社会经济的快速发展,行政事业单位越发重视内部管理,而在当前国家严厉惩治腐败的环境下,行政事业单位的内部控制问题显得尤为突出。因此,行政事业单位各级管理者要提高重视程度,充分认识当前内部控制制度建设中存在的问题,有针对性地采取措施,促进本单位健康持续地发展。本文通过对我国行政事业单位内部控制的现状阐述,剖析存在的问题,提出切实可行的对策和建议。

关键词：行政事业单位内部控制现状对策

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

海南高校社体专业校外实习基地的选择及质量监控研究

引用

体育科技 2020年第4期41卷 161-162页

作者：谢春雨海南热带海洋学院体育与健康学院海南三亚572099

文章对海南高校社体专业校外实习基地的建设进行探讨。研究认为:海南高校社体专业校外实习基地的选择要以人才培养目标为导向,以能够实现校企共赢为合作基础,以企业的经济效益和社会效益为重要参考;学生实习培养质量的提升要健全制度,... 详细信息

文章对海南高校社体专业校外实习基地的建设进行探讨。研究认为:海南高校社体专业校外实习基地的选择要以人才培养目标为导向,以能够实现校企共赢为合作基础,以企业的经济效益和社会效益为重要参考;学生实习培养质量的提升要健全制度,实施实习全程动态的监督管理,采用多元化的评价方式评估学生的实习成绩。

关键词：海南高校社体实习基地

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：