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Harnessing perennial and indeterminant growth habits for ratoon cotton(Gossypium spp.)cropping

Ecosystem Health and Sustainability 2020年第1期6卷 354-366,353页

作者： Xin Zhang Xiangjun Kong Ruiyang Zhou Zhiyong Zhang Jinbao Zhang Linsong Wang Qinglian Wang Postdocotoral Research Base Henan Collaborative Innovation Centre of Modern Biological BreedingHenan Institute of Science and TechnologyXinxiangChina Biological Postdoctoral Research Station Henan Normal UniversityXinxiangChina College of Agronomy Guangxi UniversityNanningGuangxiChina

Ratoon is the stub or root of a perennial plant that is commonly retained after harvest to produce a following crop.This paper presents a review of ratoon cotton in relation to a broader framework that has been examining perennialization of agriculture for the benefit of ecology and economy.Cotton is botanically indeterminate,but has been treated as an annual after domestication,yet the habit of perenniality is retained and the plants begin to resprout after the first harvest.In some cropping systems,this tendency is exploited using the“ratooning”practice(i.***.growing one or more crops on the rootstock of the first).Ratooning has declined for various reasons such as an increase in the prevalence of pests and diseases and overwintering risk.However,ratooning has many benefits such as no annual tillage before sowing,a well-established root system,and high yield.The three methods of ratooning offer flexibility to balance the environmental and economic benefits in agriculture.The greatest environmental benefits arise from perennial ratoon cropping of semi-wild cotton,and the greatest economic benefit is obtained from biannually cropping modern annual cultivars.However,an optimum solution would be provided by perennial cropping annual cultivars.To realize both environmental and economic benefits,research is needed in the following main areas:preventing the buildup of pests and diseases,breeding the most suitable cotton cultivars for ratooning,and developing light and simplified cultivation(LSC)systems for ratoon cultivation.

关键词： Cotton perennial indeterminant ratoon stub tropics

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浅析stub对高速连接器的影响

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机电元件 2022年第2期42卷 21-23页

作者：陈惠王超四川华丰科技股份有限公司四川绵阳621001

文章主要介绍了高速连接器中常见的stub结构,stub产生的原因,其对信号完整性中的阻抗、插入损耗、回波损耗、串扰的影响,并探讨其优化方式。

关键词：信号完整性 stub 残桩

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高速材料低损耗关键质量控制研究

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印制电路信息 2022年第S1期30卷 46-52页

作者：余少艳罗畅杜子良广州兴森快捷电路科技有限公司广东广州510663 深圳市兴森快捷电路科技股份有限公司广东深圳518057

“5G”时代为满足信息传输的高速低时延要求,25G高速材料应用急速拓展,对应PCB低损耗、信号完整性、批次间稳定性要求增加,加工管控要求增加,需对加工过程关键质量因素进行研究并控制。文章基于插入损耗研究,从不同材料的材料特性、配本... 详细信息

“5G”时代为满足信息传输的高速低时延要求,25G高速材料应用急速拓展,对应PCB低损耗、信号完整性、批次间稳定性要求增加,加工管控要求增加,需对加工过程关键质量因素进行研究并控制。文章基于插入损耗研究,从不同材料的材料特性、配本,布线方式、旋转角,蚀刻因子,介厚均匀性,铜面粗糙度,背钻stub长度等关键质量控制点进行分析,梳理出关键技术制作难点以及控制计划,为高速材料低损耗生产实现提供了方向指引。

关键词：高速材料插入损耗布线蚀刻因子 stub

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支持Modula-2远程调用的stub

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计算机工程 1992年第5期18卷 18-21,38页

作者：殷兆麟汪玉华中国矿业大学

本文介绍了支持 Modula-2远程调用两种不同的 stub及其自动生成。

关键词： Modula-2语言远程调用 stub

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A Linear Array Antenna of Microstrip Patch Antennas Fed by the Open-End of Coplanar Waveguides

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Wireless Engineering and Technology 2017年第2期8卷 37-49页

作者： Toshihisa Kamei Hiromi Shima Syotaro Fukuda Seishiro Ishii Department of Communications Engineering National Defense Academy Yokosuka Japan Kamakami Architecture Design and Quantity Surveying Office Yamagata Japan

In this study, we constructed a 4-element linear array antenna using four 20 GHz band microstrip patch antennas with a structure such that the signal is fed to the patch antennas from open-end coplanar waveguides without contact. We investigated factors related to the design of linear array patch antennas. To adjust the maximum radiation direction and reduce return loss, we optimized the spacing between the elements and their shape. With an element spacing of 11.50 mm, patch width of 3.90 mm, and patch length of 4.15 mm, we obtained a resonance frequency of 20.05 GHz and a return loss of -29.59 dB at the resonance frequency. However, in the case of a 4-element linear array antenna structure, undesired resonances occurred in frequency bands other than the design resonance frequency band of 20 GHz. To suppress these undesired resonances and obtaining stable operation at the design frequency, we propose a new structure in which the feed line is loaded with a short stub, and show through computer simulations that the occurrence of undesired resonances can be sufficiently suppressed. Furthermore, we demonstrate the problem of radiation gain reduction caused by introducing a short stub, propose a design method for a new structure in which the feed line has slits between the stubs, and show improvement of the antenna gain by 0.5 dBi.

关键词： Microstrip Patch Antenna Coplanar Waveguide Linear Array Antenna Short stub Undesired Resonance Suppression

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Broadband Miniaturized Bandpass Filter with Circular stubs for Compact Wireless and Mobile Communication Systems

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Journal of Electromagnetic Analysis and Applications 2013年第3期5卷 109-113页

作者： Yulan Zhang Heather Song Department of Electrical and Computer Engineering University of Colorado Colorado Springs USA. Intel Co. Hillsboro USA

A miniaturized square resonator bandpass filter with circular stubs is designed, fabricated, and characterized. Analytical calculations were carried out to determine the critical filter parameters and the design was optimized using a 3D electromagnetic finite-element solver. The measured results were in good agreement with the designed results. The proposed filter exhibits significant improvement in bandwidth compared to the conventional square resonator bandpass filters.

关键词： Miniaturized Square Resonator Bandpass Filter Circular stub Electromagnetic Simulation

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Effective Size Reduction Technique for Microstrip Filters

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Journal of Electromagnetic Analysis and Applications 2013年第4期5卷 166-174页

作者： Dhirendra Kumar Asok De ECE Department Maharaja Agrasen Instititute of Technology Delhi India NIT Patna India.

In this paper an effective size reduction technique using fractal structure is suggested. The proposed technique has been applied on a band stop and a low pass filter separately. This technique provides 42% reduction of size for the band stop filter and about 26% for the low pass counterpart. Both the designed structures are fabricated and the measured results are compared with the simulated results. The proposed technique does not require any recalculation or optimization of dimensions of the filter, and is straightforward to implement. The band stop filter is designed for the center frequency of 3 GHz where as the cut-off frequency for low pass filter is 2.5 GHz. A good agreement between the simulated and measured results is observed. A comprehensible explanation of the proposed technique is also provided.

关键词： Band Stop Filter Fractal Structures Kotch Curve Low Pass Filters Open stub Step Impedance Network

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ALLERGY AND IMMUNOLOGY

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China Medical Abstracts(Internal Medicine) 2007年第1期24卷 8-11页

4.1 Autoimmune Disease2007019 The clinical significance of epitopes of SmB and SmD in systemic lupus erythemotosus. XUE Jing(薛静), et al. Dept Rheumotol, 2nd Affili Hosp, Sch Med, Zhejiang Univ, Hangzhou 310008. Chin J Lab Med 2006;29(11):996-1000. Objective To assess the presence of autoantibodies directed against the epitopes of stub and SmD in systemic lupus erythemotosus (SLE) as well as other different connective tissue diseases (CTDs) and analyze their clinical significance .