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Light interception and radiation use efficiency response to tridimensional uniform sowing in winter wheat 被引量:10
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作者 tao zhi-qiang wang de-mei +3 位作者 ma shao-kang yang yu-shuang zhao guang-cai chang xu-hong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第3期566-578,共13页
Improving radiation use efficiency (RUE) of the canopy is necessary to increase wheat (Triticum aesfivum) production. Tridimensional uniform sowing (U) technology has previously been used to construct a uniforml... Improving radiation use efficiency (RUE) of the canopy is necessary to increase wheat (Triticum aesfivum) production. Tridimensional uniform sowing (U) technology has previously been used to construct a uniformly distributed population structure that increases RUE. In this study, we used tridimensional uniform sowing to create a wheat canopy within which light was spread evenly to increase RUE. This study was done during 2014-2016 in the Shunyi District, Beijing, China. The soil type was sandy loam. Wheat was grown in two sowing patterns: (1) tridimensional uniform sowing (U); (2) conventional drilling (D). Four planting densities were used: 1.8, 2.7, 3.6, and 4.5 million plants ha-1. Several indices were measured to compare the wheat canopies: photosynthetic active radiation intercepted by the canopy (IPAR), leaf area index (LAI), leaf mass per unit area (LMA), canopy extinction coefficient (K), and RUE. In two sowing patterns, the K values decreased with increasing planting density, but the K values of U were lower than that of D. LMA and IPAR were higher for U than for D, whereas LAI was nearly the same for both sowing patterns. IPAR and LAI increased with increasing density under the same sowing pattern. However, the difference in IPAR and LAI between the 3.6 and 4.5 million plants ha-1 treatments was not significant for both sowing patterns. Therefore, LAI within the same planting density was not affected by sowing pattern. RUE was the largest for the U mode with a planting density of 3.6 million plants ha-1 treatment. For the D sowing pattern, the lowest planting density (1.8 million plants ha-1) resulted in the highest yield. Light radiation interception was minimal for the D mode with a planting density of 1.8 million plants ha-1 treatment, but the highest RUE and highest yield were observed under this condition. For the U sowing pattern, IPAR increased with increasing planting density, but yield and RUE were the highest with a planting density of 3.6 million plants ha-1. These results indicated that the optimal planting density for improving the canopy light environment differed between the sowing patterns. The effect of sowing patternxplanting density interaction on grain yield, yield components, RUE, IPAR, and LMA was significant (P〈0.05). Correlation analysis indicated that there is a positive significant correlation between grain yield and RUE (t=0.880, P〈0.01), LMA (r=0.613, P〈0.05), andspike number (t=0.624, P〈0.05). These results demonstrated that the tridimensional uniform sowing technique, particularly at a planting density of 3.6 million plants ha-0, can effectively increase light interception and utilization and unit leaf area. This leads to the production of more photosynthetic products that in turn lead to significantly increased spike number (P〈0.05), kernel number, grain weight, and an overall increase in yield. 展开更多
关键词 tridimensional uniform sowing extinction coefficient leaf area index leaf mass per unit area WHEAT
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Study of Current Sheath Velocity and Its Distribution Using Tridimensional Magnetic Probe in Sahand Plasma Focus
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作者 M.A.MOHAMMADI S.HEDYEH 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第5期353-357,共5页
The current sheath velocity in 0.25 Torr gas pressure of Filippov type plasma focus is studied experimentally. By using two tridimensional magnetic probes on top of the anode surface, the current sheath velocity is me... The current sheath velocity in 0.25 Torr gas pressure of Filippov type plasma focus is studied experimentally. By using two tridimensional magnetic probes on top of the anode surface, the current sheath velocity is measured for argon, oxygen and nitrogen. Additionally, the effect of charging voltage on the current sheath velocity is studied in both axial and radial phases. We found that, the maximum current sheath velocities at both radial and axial phases are respectively 4.33 ± 0.28 (cm/μs) and 3.92 ± 0.75 (cm/μs) with argon as the working gas at 17 kV. Also, the minimum values of current sheath velocity are 1.48 ± 0.15 (cm/μs) at the radial phase and 1.14 ± 0.09 (cm/μs) at the axial phase with oxygen at 12 kV. The current sheath velocity at the radial phase is higher than that at the axial phase for all gases and voltages. In this study, variation of the full width half maximum (FWHM) of magnetic probe signals with voltage is investigated for different gases at radial and axial phases. 展开更多
关键词 plasma focus tridimensional magnetic probe current sheath dynamics
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Research Progress and Present Situation of Tridimensional Reservoir Development
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作者 Xu Ning Guo Xiuwen He Chengchen 《China Oil & Gas》 CAS 2013年第4期20-25,共6页
Designing special well patterns, tridimensional reservoir development selects a variety of wells and uses the gravity energy to maximize the hydrocarbon recovery. It's a new development model to implement the oil ... Designing special well patterns, tridimensional reservoir development selects a variety of wells and uses the gravity energy to maximize the hydrocarbon recovery. It's a new development model to implement the oil and gas exploitation economically and efficiently. It is suitable for both huge oiliness altitude reservoirs and large dip-angle sandstone reservoirs, and more for the carbonate reservoirs developed in high-angle fractures, volcanic reservoirs and metamorphic reservoirs. 展开更多
关键词 Research Progress and Present Situation of tridimensional Reservoir Development
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基于MDA的TRISO-Model模型管理方法及应用 被引量:6
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作者 袁峰 李明树 《软件学报》 EI CSCD 北大核心 2007年第7期1612-1625,共14页
TRISO-Model(tridimensional integrated software development model)是为处理软件开发的复杂性和动态性而提出的三维集成软件开发方法学,其中,多维模型之间的语义一致性维护以及对模型应用中公共操作部分的重用,提出了基于一致语义进... TRISO-Model(tridimensional integrated software development model)是为处理软件开发的复杂性和动态性而提出的三维集成软件开发方法学,其中,多维模型之间的语义一致性维护以及对模型应用中公共操作部分的重用,提出了基于一致语义进行模型管理的需求.给出了基于MDA(model driven architecture)进行模型管理的方法MDA-MMMethod(MDA based model management method),应用MDA的4层模型管理结构,基于MDA核心标准MOF(meta object facility)所提供的公共语义基础管理模型和元模型,MDA-MMMethod支持各种MDA模型操作标准实现在TRSIO-model应用中的重用.开发了相应的支持系统MDA-MMSystem(MDA based model management system),应用于SoftPM的项目实践中.与传统方法相比,模型应用的开发效率得到了显著提高,同时降低了开发成本.最后,给出了模型融合的应用实例介绍. 展开更多
关键词 TRISO-model(tridimensional integrated software development model) MDA(model driven architecture) MOF(meta object facility)元建模 模型转换
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Three-dimensional endoanal ultrasound for diagnosis of perianal fistulas: reliable and objective technique 被引量:7
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作者 Marina Garcés-Albir Stephanie Anne García-Botello +4 位作者 Alejandro Espi Vicente Pla-Martí Jose Martin-Arevalo David Moro-Valdezate Joaquin Ortega 《World Journal of Gastrointestinal Surgery》 SCIE CAS 2016年第7期513-520,共8页
AIM: To evaluate accuracy of three-dimensional endoanal ultrasound(3D-EAUS) as compared to 2D-EAUS and physical examination(PE) in diagnosis of perianal fistulas and correlate with intraoperative findings. METHODS: A ... AIM: To evaluate accuracy of three-dimensional endoanal ultrasound(3D-EAUS) as compared to 2D-EAUS and physical examination(PE) in diagnosis of perianal fistulas and correlate with intraoperative findings. METHODS: A prospective observational consecutive study was performed with patients included over a two years period. All patients were studied and operated on by the Colorectal Unit surgeons. The inclusion criteria were patients over 18, diagnosed with a criptoglandular perianal fistula. The PE, 2D-EAUS and 3D-EAUS was performed preoperatively by the same colorectal surgeon at the outpatient clinic prior to surgery and the fistula anatomy was defined and they were classified in intersphincteric, high or low transsphincteric, suprasphincteric and extrasphincteric. Special attention was paid to the presence of a secondary tract, the location of the internal opening(IO) and the site of external opening. The results of these different examinations were compared to the intraoperative findings. Data regarding location of the IO, primary tract, secondary tract, and the presence of abscesses or cavities wasanalysed.RESULTS: Seventy patients with a mean age of 47years(range 21-77), 51 male were included. Low transsphincteric fistulas were the most frequent type found(33, 47.1%) followed by high transsphincteric(24,34.3%) and intersphincteric fistulas(13, 18.6%). There are no significant differences between the number of IO diagnosed by the different techniques employed and surgery(P > 0.05) and, there is a good concordance between intraoperative findings and the 2D-EAUS(k= 0.67) and 3D-EAUS(k = 0.75) for the diagnosis of the primary tract. The ROC curves for the diagnosis of transsphincteric fistulas show that both ultrasound techniques are adequate for the diagnosis of low transsphincteric fistulas, 3D-EAUS is superior for the diagnosis of high transsphincteric fistulas and PE is weak for the diagnosis of both types.CONCLUSION: 3D-EAUS shows a higher accuracy than 2D-EAUS for assessing height of primary tract in transsphincteric fistulas. Both techniques show a good concordance with intraoperative finding for diagnosis of primary tracts. 展开更多
关键词 tridimensional endoanal ULTRASOUND high transsphincteric FISTULA PERIANAL FISTULA intersphinteric FISTULA DIMENSIONAL endoanal ULTRASOUND
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Case Report: Caseous Calcification of the Mitral Annulus in an 88-Year-Old Woman
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作者 Giuseppe Fede Giuseppe Abate +8 位作者 Paola Belluardo Carmelo Di Tommasi Maria Luisa Guarrella Nicoletta Guccione Guglielmo Piccione Salvatore Solarino Giuseppe Sulsenti Giovanni Tasca Sabina Ficili 《Open Journal of Internal Medicine》 2020年第4期337-341,共5页
The caseous calcification of the mitral annulus (CCMA) is a rare variant of the mitral annulus calcification (MAC), with prevalence of 0.067% in general population. It is usually an asymptomatic condition but rarely i... The caseous calcification of the mitral annulus (CCMA) is a rare variant of the mitral annulus calcification (MAC), with prevalence of 0.067% in general population. It is usually an asymptomatic condition but rarely it can cause severe mitral valve dysfunction, embolization, and conduction abnormalities. Transthoracic echocardiography (TTE) is a useful diagnostic tool. However, it can be necessary a multi-modality imaging approach for a differential diagnosis among other intra-cardiac masses. We are presenting a case of CCMA in an 88-year-old woman admitted to our department for acute decompensation of chronic heart failure. TTE has shown pathognomonic findings of CCMA. Tridimensional trans-esophageal echocardiography (3D TEE) gave a better characterization of the CCMA, avoiding further diagnostic procedures. 展开更多
关键词 Mitral Valve Caseous Calcification tridimensional Echocardiography
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The Contribution of Waves in Mixing Processes of the Patos Lagoon Plume
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作者 Eduardo de Paula Kirinus Wiliam Correa Marques +1 位作者 Julliet Correa da Costa Elisa Helena Leao Fernandes 《International Journal of Geosciences》 2012年第5期1019-1026,共8页
The analysis of wave effects above salinity is important in order to define mixing processes and their potential to change density gradients, since action in the region of the Patos Lagoon plume is highly dynamic. Thi... The analysis of wave effects above salinity is important in order to define mixing processes and their potential to change density gradients, since action in the region of the Patos Lagoon plume is highly dynamic. This paper aims to evaluate the influence of waves on the mixing pattern of the adjacent continental shelf. Constantly marked by tides and circulation variations, changing from flood to ebb tide, salinity stands as a major parameter for analysis. The study is based on hydrodynamic numerical modeling experiments using the TELEMAC3D model and waves generated by the wind using the TOMAWAC coupled model. The comparison between the situations considering the waves generated by the wind and without waves was made through time series analysis, stratification series, transversal cross sections, longitudinal cross sections, salinity mean fields and diagrams by Richardson and Brünt-V?is?l?s frequency parameters. With the cross sections analysis, the mixing effect generated by the waves was observed, demonstrating clearly that the waves were capable of raising the superficial salinity in regions far from the Patos Lagoon entrance, while at the entrance, the wave effects enhanced the mixing on the deepest layers, decreasing the saline intrusion and expanding the plume more radially on the surface. The space-temporal diagrams were effective to demonstrate the modulation effect of the waves over the salt mixing of saline waters, revealing that wave effects decrease the stratification as well as the Brünt-V?is?l?s frequency and increase the period of buoyancy, due to the mixing increase. 展开更多
关键词 Vertical Mixing tridimensional Numerical Modeling STRATIFICATION
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A Study of Agricultural Tridimension Pollution and Discussion on Its Control 被引量:4
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作者 ZHANGLi-jian CAIDian-xiong WANGXiao-bin ZHANGJian-jun JINKe 《Agricultural Sciences in China》 CAS CSCD 2005年第3期214-223,共10页
The paper outlines the background of the research on control of agriculture tridimensional pollution and its tendency.The new concept of agricultural tridimension pollution (ATriP) with its control theory is initiall... The paper outlines the background of the research on control of agriculture tridimensional pollution and its tendency.The new concept of agricultural tridimension pollution (ATriP) with its control theory is initially proposed as a result ofcontinuously increased agricultural pollution within the systems of hydrosphere, pedosphere, biosphere and atmospheredue to improper use of agricultural management measures. Furthermore, the high priority of the next 5-10 years nationalresearch domains and areas, and techniques for strengthening of ATriP prevention and control is discussed. 展开更多
关键词 Agricultural tridimension pollution (ATriP) Pollution-filtering technology Pollution governance Synthetic study
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