检索结果-南通市图书馆

Late Pliocene diversity and distribution of Drynaria(Polypodiaceae) in western Yunnan explained by forest vegetation and humid climates

在线全文

学校读者我要写书评

暂无评论

Plant Diversity 2016年第4期38卷 194-200页

作者： Yong-jiang huang Tao Su Zhe-Kun Zhou Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences

The palaeodiversity of flowering plants in Yunnan has been extensively interpreted from both a molecular and fossil perspective. However, for cryptogamic plants such as ferns, the palaeodiversity remains poorly known. In this study, we describe a new ferny fossil taxon, Drynaria lanpingensis sp. nov. huang,Su et Zhou(Polypodiaceae), from the late Pliocene of northwestern Yunnan based on fragmentary frond and pinna with in situ spores. The frond is pinnatifid and the pinnae are entirely margined. The sori are arranged in one row on each side of the primary vein. The spores have a semicircular to bean-shaped equatorial view and a tuberculate surface. Taken together with previously described fossils, there are now representatives of three known fossil taxa of Drynaria from the late Pliocene of western *** finds suggest that Drynaria diversity was considerable in the region at that time. As Drynaria is a shade-tolerant plant, growing preferably in wet conditions in the understory of forests, its extensive existence may indicate forest vegetation and humid climates in western Yunnan during the late *** is in line with results from floristic investigations and palaeoclimatic reconstructions based on fossil floras.

关键词： Biodiversity Fern Drynaria In sire spore Late Pliocene Yunnan

Relationship of 2 100-2 300 nm Spectral Characteristics of Wheat Canopy to Leaf Area Index and Leaf N as Affected by Leaf Water Content

在线全文

学校读者我要写书评

暂无评论

Pedosphere 2006年第3期16卷 333-338页

作者： ZHAO Chun-jiang WANG Ji-Hua LIU Liang-Yun huang Wen-jiang ZHOU Qi-Fa National Engineering Research Center for Information Technology in Agriculture Beijing 100089 （China） The State Key Laboratory of Plant Physiology and Biochemistry College of Life Sciences Zhejiang University Hangzhou 310012 （China）

The effects of leaf water status in a wheat canopy on the accuracy of estimating leaf area index (LAI) and N were determined in this study using extracted spectral characteristics in the 2 000-2 300 nm region of the short wave infrared (SWI) band. A newly defined spectral index, relative adsorptive index in the 2000-2300 nm region (RAI2000-2300), which can be calculated by RAI2000-2300 = (R2224 - R2054) (R2224 + R2054)-1 with R being the reflectance at 2224 or 2054 nm, was utilized. This spectral index, RAI2000-2300, was significantly correlated (P < 0.01) with green LAI and leaf N concentration and proved to be potentially valuable for monitoring plant green LAI and leaf N at the field canopy scale. Moreover, plant LAI could be monitored more easily and more successfully than plant leaf N. The study also showed that leaf water had a strong masking effect on the 2 000-2 300 nm spectral characteristics and both the coefficient between RAI2000-2300 and green LAI and that between RAI2000-2300 and leaf N content decreased as leaf water content increased.

关键词： leaf area index nitrogen plant water status reflectance Triticum aestivum L.

Responses of Guangdong coastal upwelling to the summertime typhoons of 2006

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2012年第3期55卷 495-506页

作者： PAN AiJun GUO XiaoGang XU JinDian huang jiang WAN XiaoFang Ocean Dynamics Laboratory Third Institute of OceanographyState Oceanic Administration(TIOSOA)Xiamen 361005China

The effects of typhoon intrusion on the Guangdong coastal upwelling system were investigated on the basis of in situ CTD （conductivity-temperature-depth） cruise observations and especially upward-looking ADCP （Acoustic Doppler Current Profilers） measurements obtained from a comprehensive survey of the Guangdong coastal region carded out by the Chinese Off- shore Investigation and Assessment Project in the summer of 2006. It was found that northeastward geostrophic advection driven by the summer monsoon has a significant near-seabed onshore component adjacent to Shantou, which in conjunction with upper-level offshore Ekman flow, constitutes the canonical Guangdong coastal upwelling system. Further analyses suggested that the Guangdong coastal upwelling system is sensitive to subtle changes in the typhoon intensity and migration pathway. On one hand, as a typhoon approaches from north of the upwelling system （e.g. Typhoon 0604 （Bilis） and Typhoon 0605 （Kaemi）） in the early phase of inmasion, the enhanced southwesterly leads to exceptional enhancement of the onshore flow; i.e., enhanced upwelling. Afterward, irrespective of the forced ocean responses resulting from the stronger local winds （Typhoon 0604） or the moderate typhoon-induced inertial oscillations （Typhoon 0605）, the situation is not conducive to sustaining a stable, persistent upwelling system. On the other hand, when there is typhoon intrusion south of the upwelling system （e.g. Typhoon 0606 （Prapiroon））, the favorable southwesterly tends to be substituted by an anomalous northeasterly, which destroys the traditional coastal upwelling pattern. However, the canonical upwelling system tends to recover within 1-2 days of the typhoon passing.

关键词： typhoon coastal upwelling inertial oscillation Ekman flow geostrophic advection

Microfluidic sequential injection analysis system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2012年第4期55卷 531-536页

作者： FAN JiFeng ZHU Ying SHI XiaoTong FANG Qun huang jiang Institute of Microanalytical Systems Department of ChemistryZhejiang UniversityHangzhou 310058China Research Center for Analytical Instrumentation Institute of Cyber-Systems and ControlState Key Laboratory of Industrial Control TechnologyZhejiang UniversityHangzhou 310058China

A sequential injection analysis (SIA) system based on polydimethylsiloxane (PDMS) chip with integrated pneumatic-actuated valves was developed. A novel SIA operation mode using multiphase laminar flow effect and pneumatic microvalve control was proposed. The sample and reagent solutions were synchronously loaded and injected in the chip-based sample injection module instead of multi-step sequential injection by a multiposition valve and a reciprocating pump as in conventional SIA system. The sample and reagent injection volumes were reduced to ca. 1.1 nL. The present system has the advantages of simple structure, fast and convenient operation, low sample and reagent consumption, and high degree of integration and automation. The system operation conditions were optimized using fluorescein as model sample. Its feasibility in biological analysis was preliminarily demonstrated in enzyme inhibition assay.

关键词： microfluidic chip PDMS chip pneumatic-actuated valve sequential injection analysis

Sports video summarization and adaptation for application in mobile communication

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 819-829页

作者： GAO Wen huang Qing-ming jiang Shu-qiang ZHANG Peng Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Graduate School Chinese Academy of Sciences Beijing 100039 China Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China Institute of Computing Technology Chinese Academy of Sciences Beijing 100080 China

Sports video appeals to large audiences due to its high commercial potentials. Automatically extracting useful semantic information and generating highlight summary from sports video to facilitate users' accessing requirements is an important problem, especially in the forthcoming broadband mobile communication and the need for users to access their multimedia information of interest from anywhere at anytime with their most convenient digital equipments. A system to generate highlight summaries oriented for mobile applications is introduced, which includes highlight extraction and video adaptation. In this system, several highlight extraction techniques are provided for field sports video and racket sports video by using multi-modal information. To enhance users' viewing experience and save bandwidth, 3D animation from highlight segment is also generated. As an important procedure to make video analysis results universally applicable, video transcoding techniques are applied to adapt the video for mobile communication environment and user preference. Experimental results are encouraging and show the advantage and feasibility of the system for multimedia content personalization, enhancement and adaptation to meet different user preference and network/device requirements.

关键词： Adaptive systems Animation Bandwidth Equipment Multimedia systems Requirements engineering Semantics Three dimensional

Smoothing methods based on coordinate transformation in a linear space and application in airfoil aerodynamic design optimization

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2015年第2期58卷 297-306页

作者： WANG Chao GAO Zheng Hong huang jiang Tao ZHAO Ke LI Jing National Key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University China Aerodynamics Research & Development Center

In detailed aerodynamic design optimization,a large number of design variables in geometry parameterization are required to provide sufficient flexibility and obtain the potential optimum ***,with the increasing number of design variables,it becomes difficult to maintain the smoothness on the surface which consequently makes the optimization process progressively *** this paper,smoothing methods based on B-spline functions are studied to improve the smoothness and design *** wavelet smoothing method and the least square smoothing method are developed through coordinate transformation in a linear space constructed by B-spline basis *** these two methods,smoothing is achieved by a mapping from the linear space to itself such that the design space remains unchanged.A design example is presented where aerodynamic optimization of a supercritical airfoil is conducted with smoothing methods included in the optimization *** results from the design example confirm that these two smoothing methods can greatly improve quality and efficiency compared with the existing conventional non-smoothing method.

关键词： smoothness linear space B-spline functions coordinate transformation wavelet least square aerodynamicoptimization

在线全文

学校读者我要写书评

暂无评论

消防机器人灭火救援应用及发展探究

中国高新科技 2024年第3期 38-40页

作者：朱波郭骁尹军黄江张盛黄冈大别山发电有限责任公司湖北麻城438300

文章以消防机器人灭火救援应用及发展为研究对象,首先简单介绍了项目情况,随后结合实际项目,从消防机器人的研发应用入手,分析了其中的一些研发技术应用内容,最后探讨了消防机器人灭火救援应用及发展,以期为相关研究提供参考。

关键词：消防机器人灭火救援应用发展

在线全文

学校读者我要写书评

暂无评论

无机化学锚栓在建筑幕墙工程中的应用

工程建设与设计 2024年第2期 158-160页

作者：黄友江吴辉王小勇广东潮威建设工程有限公司广东珠海510095

以广发银行总部大楼中国人寿大厦项目幕墙安装项目为依托,对无机化学锚栓的锚固和破坏机理进行研究,结合项目实际情况提出无机化学锚栓的施工工艺,并进行了现场承载力试验,为幕墙工程中无机化学锚栓的应用研究提供参考。

关键词：无机化学锚栓幕墙工程锚固机理破环机理施工工艺

维普期刊数据库博看期刊

Particle Measurement Sensor for in situ determination of phase structure of fluidized bed

在线全文

学校读者我要写书评

暂无评论

Particuology 2009年第3期7卷 175-182页

作者： Qiang Zhang Cang huang Dong jiang Xiaobo Wei Zhen Qian Fei Wei Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical Engineering Tsinghua University Beijing 100084 China

Based on three-dimensional （3D） acceleration sensing, an intelligent particle spy capable of detecting, transferring, and storing data, is proposed under the name of Particle Measurement Sensor （PMS）. A prototype 60-mm-dia PMS was tested to track its freefall in terms of velocity and displacement, and served as a particle spy in a fluidized bed delivering the in situ acceleration information it detects. With increasing superficial gas velocity in the fluidized bed, the acceleration felt by PMS was observed to increase. The variance of the signals, which reflect the fluctuation, increased at first, reaching a maximum at the gas velocity （Uc） which marks the transition from bubbling to turbulent fluidization. Through probability density distribution （PDD） analysis, the PDD peak can be divided into the emulsion phase peak and the bubble phase peak. The average acceleration of emulsion and bubble phase increased, while the variance of both phases reached a maximum at Uc, at the same time. However, the difference between the variances of two phases reached the maximum at Uc. Findings of this study indicate that PMS can record independent in situ information. Further, it can provide other in situ measurements when equipped with additional multi-functional sensors.

关键词： Particle Measurement Sensor Fluidized bed Acceleration Gas-solid two-phase flow Phase structure