检索结果-南通市图书馆

HYDRUS-2D simulations of water movement in a drip irrigation system under soilless substrate

1988年

作者：巴洛(Barlow.c.w.) 艾森(Eisen G.p.)

来源：南通市图书馆图书汇雅图书（南通市图书馆... 评论

在线全文

汇雅图书（南通市图书馆）

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2022年第3期15卷 210-216页

作者： Lei Geng Li Li wei Li chengfei Yang Fanjia Meng Key Laboratory of Agricultural Information Acquisition Technology Ministry of Agriculture and Rural AffairsChina Agricultural UniversityBeijing100083China Key Laboratory of Smart Agriculture System Integration Ministry of EducationChina Agricultural UniversityBeijing 100083Chin

A comprehensive understanding of the distribution and water movement of the substrate in root areas is crucial to the design and management of drip irrigation systems,which is a significant step to maximizing crop water use efficiency by understanding the hydrodynamics in soilless *** this study,an improved HYDRUS-2D model by the dynamic root growth model was used to simulate water movement under the condition of drip irrigation and the water uptake process of the root,and then,compared with the observed *** water content under drip irrigation was also measured with the calibrated EcH20-Ec5 *** situation of substrate water movement was analyzed under the conditions of different depths,different initial water content,and different irrigation *** substrate water movement under different drip irrigation conditions was *** results showed that incorporating the defined initial and boundary conditions and the hydraulic characteristics of the substrate into the model enabled HYDRUS model to predict the movement and position of water in unsaturated porous media by solving Richards *** drip irrigation,the substrate wetting body was approximately a quarter ellipse,and the water would continue to move to the area where the wetting front did not reach within 1 h after *** simulation results of the improved HYDRUS-2D model agreed well with those observed by the EcH2O-Ec5 sensors,and the model could provide a basis for precision irrigation of soilless substrate culture under drip irrigation.

关键词： drip irrigation HYDRUS-2D substrate water movement soilless substrate

Research of changbai mountain panax ginseng's ginsenoside compound and relevant enzyme gene expression network interaction

在线全文

学校读者我要写书评

暂无评论

Research of Changbai mountain Panax ginseng's ginsenoside co...

Discrimination and stratification tests of cardiovascular disease risk assessment models against ultrasound detection of carotid plaques in type 2 diabetics

第十一届全国植物基因组学大会

作者： w.Liu~#,c.Li~#,Y.Yu,S.Jiang,Y.wang,M.Zhang~* Jilin Agricultural University,changchun,130118,p.R.china

changbai mountain panax ginseng as the material,I have extracted the ginsenosides in 15 different organs of 5 years old with soxhlet,and then determinated the content of ginseng in different organs by high performance...

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Health 2013年第7期5卷 1-10页

作者： Lawrence w. c. chan Yu Sun Iris F. F. Benzie Department of Health Technology and Informatics Hong Kong Polytechnic University Hung Hom China

Atherosclerosis is the early stage of arterial disease, and underlies development of cardiovascular disease (cVD) and stroke. Although sophisticated models for assessing cVD and stroke risk have been derived based on large-scale prospective studies, their abilities in detecting the presence or absence of atherosclerotic plaque have not been investigated. This study aimed to evaluate and compare discriminatory and risk stratifying abilities of 13 cVD risk assessment models against the ultrasound detection of carotid plaques in type 2 diabetes mellitus (T2DM) patients. Forty-nine T2DM subjects were recruited with informed consent, and major anthropomorphic and biomarker data for these models were collected. The model risk scores were evaluated against the carotid plaques detected by Doppler ultrasound. Only the FHS-Lpts-cHD-10Y model, which is a variant of the Framingham model, revealed an area under the receiver operating curve (AUROc) that was significantly different from a random scoring approach (AUROc: 0.681, p was able to stratify the risk levels of carotid plaque presence (chi-Square statistic: 5.99,

关键词： Atherosclerosis cardiovascular Disease Doppler Ultrasound Risk Assessment

Thermodynamic calculation of Segregation in Multicomponent Steels

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

Journal of Materials Science & Technology 1996年第3期12卷 238-240页

作者： Li, L Delaey, L wollants, p Biest, VD KATHOLIEKE UNIV LEUVEN DEPT MTMB-3001 HEVERLEEBELGIUM

The thermodynamic equation for segregation in multicomponent steels is extended from that in ternary system and the segregation amounts of cr, c and p in the intergranular phase in a cr-steel are estimated.

关键词： REGULAR SOLUTION MODEL pHASES

The Least Order Observer Based Sensorless control of pMSG in Direct-Drive wind Turbines

在线全文

学校读者我要写书评

暂无评论

Journal of Energy and power Engineering 2011年第7期5卷 665-670页

作者： S.Y. Yang X. Zhang c.w. Zhang Z. Xie School of Electrical Engineering and Automation Hefei University of Technology Hefei 230009 China

permanent magnet synchronous Generator （pMSG） based direct-drive wind energy conversion system （w.c.） has been attracting wide attentions. For the special application, sensorless control for pMSG is desired. By widely studying the previous contributes, a novel estimator based on back-EMF is proposed. The estimator is composed of back-EMF observer and a phase-lock-loop （pLL） control to get the rotor-flux speed and position. The estimator not only can be used for interior and surface permanent magnet synchronous generators, but also has a compact and symmetrical structure, which makes it be beneficial for implementation. compared with previous strategies, the EMF observer is independent of the pLL control, which would simplify the observer design. Meanwhile, the proposed estimator is less sensitive to parameter variations. Based on mathematic models of pMSG, the proposed estimator was analyzed in detail, and the realizing process was also presented. To validate the proposed estimator, the important experiment results are reported.

关键词： Back-EMF pLL pMSG sensorless control wind energy conversion system.

wEED cONTROL IN SUMMER-SOwING SOYBEAN wITH FLUMIOXAZIN pLUS AcETOcHLOR AND FLUMIcLORAc-pENTYL pLUS cLETHODIM

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

WEED CONTROL IN SUMMER-SOWING SOYBEAN WITH FLUMIOXAZIN PLUS ...

Impact of thermostat on interfacial thermal conductance prediction from non-equilibrium molecular dynamics simulations

The 18th Asian-pacific weed Science Society conference

作者： J.c.Han M.Q.wang H.p.Liu p.Y.Guo college of Agronomy Shanxi Agricultural University

Field experiments were conducted at Taigu,Shanxi province,to evaluate the efficacy of flumioxazin plus acetochlor and flumiclorac-pentyl plus clethodim applied preemergence and postemergence in summer-sowing *** showed that tank-mixing flumioxazin at 50g ai/ha and acetochlor at 800g ai/ha was an effective soilapplied herbicide for weed control in *** control efficacy was better than applied alone,and no injury was found to soybean and the following crop wheat. Flumiclorac-pentyl at 50g ai/ha plus clethodim at 70g ai/ha could suppress both broadleaf weeds and grass weeds with an efficacy of more than 90%.Flumicloracpentyl applied alone or incorporated caused some injury to soybean seedlings,but soybean recovered 2-3 weeks after treatment and no affect was found to the yield.

关键词： Flumiclorac-pentyl flumioxazin soybean tank mixing weed control

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

chinese physics B 2022年第5期31卷 561-568页

作者： Song Hu c Y Zhao Xiaokun Gu Institute of Engineering Thermophysics School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The knowledge of interfacial thermal conductance(ITc)is key to understand thermal transport in *** non-equilibrium molecular dynamics(NEMD)simulation is a useful tool to calculate the *** this study,we investigate the impact of thermostat on the prediction of the *** Langevin thermostat is found to result in larger ITc than the Nose-Hoover *** addition,the results from NEMD simulations with the Nose-Hoover thermostat exhibit strong size effect of thermal *** spectral heat flux decomposition and modal temperature calculation reveal that the acoustic p.onons in hot and cold thermal reservoirs are of smaller temperature difference than optical p.onons when using the Nose-Hoover thermostat,while p.onons in the Langevin thermostat are of identical *** a nonequilibrium state of p.onons in the case of the Nose-Hoover thermostat reduces the heat flux of low-to-middle-frequency *** also discuss how enlarging the reservoirs or adding an epitaxial rough wall to the reservoirs affects the predicted ITc,and find that these attempts could help to thermalize the p.onons,but still underestimate the heat flux from low-frequency p.onons.

关键词： interfacial thermal conductance p.onon transport molecular dynamics

Design, Analysis and Installation of Offshore Instrumented Moored Data Buoy System

在线全文

学校读者我要写书评

暂无评论

Journal of Shipping and Ocean Engineering 2015年第4期5卷 181-194页

作者： Kaliyaperumal p., Venkatesan R., Senthilkumar, p Kalaivanan, c. K. Gnanadhas, T Vedachalam, N. Ocean Observation Systems Earth Science Systems Organization-National Institute of Ocean Technology ChennaL 600100 India

This paper discusses the analysis done on the meteorological ocean buoy mooring used for monitoring the Indian seas. Based on the extreme environmental parameters experienced by the buoys, mooring loads are analyzed using offshore dynamic analysis software. The results obtained are validated with the tension recorder installed in one of the moorings, and the results are found to comply with an accuracy of better than 1%. The successful on demand performance of the mooring during major cyclones in the Bay of Bengal and the vital meteorological and oceanographic information provided by the buoy during these disastrous cyclonic events validates the mooring design, and proves the data availability for societal needs. The time critical data assimilated in the cyclone prediction models have given confidence to improve the country＇s weather prediction and climate modelling capabilities.

关键词： Mooring data buoy tsunami cyclone.

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

基于双层连通性检测的路面裂缝图像去噪算法

公路交通科技 2015年第11期32卷 7-13,26页

作者：彭博罗楠欣蒋阳升陈成 K c p wANG 重庆交通大学交通运输学院重庆400074 西南交通大学交通运输与物流学院四川成都610031 西南交通大学综合运输四川省重点实验室四川成都610031 西南交通大学综合交通运输智能化国家地方联合工程实验室四川成都610031 School of civil&Environmental Engineering Oklahoma State UniversityOK74078USA

为了消除路面裂缝图像中的孤立噪声并保护裂缝边缘的细致特征,本文基于像素和裂缝子块两个层级的连通性检测设计了去噪算法,主要包括3个部分：（1）像素连通性检测,剔除连通性差的像素;（2）孤岛噪声消除算法,删除相对孤立的目标区域;（... 详细信息

为了消除路面裂缝图像中的孤立噪声并保护裂缝边缘的细致特征,本文基于像素和裂缝子块两个层级的连通性检测设计了去噪算法,主要包括3个部分：（1）像素连通性检测,剔除连通性差的像素;（2）孤岛噪声消除算法,删除相对孤立的目标区域;（3）8×8裂缝子块去噪算法。然后,提出了算法流程并探讨参数的选择。最后,应用Visual Studio 2008和Open cV编程对本文算法、常用的中值滤波去噪法、长线段和黑色像素比例法进行性能测试,结果表明,本文算法可有效消除孤立噪声并保持边缘连续性,具有更高的准确率（85.06%）和召回率（85.80%）,综合性能指标F1值比后两者分别高0.74%~19.19%和0.20%~12.06%。

关键词：道路工程路面裂缝去噪算法图像处理连通性检测