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改变小麦迟收习惯,减少田间落粒损失
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作者 彭婷婷 陈若礼 《农技服务》 2014年第7期244-244,共1页
小麦收获过晚,在田间易落粒,麦田土壤墒情好,麦田中脱落的麦粒也随之出苗生长。作者通过统计小麦收获后麦田的出麦苗数,进一步估算了麦田脱落的麦粒数和产量损失,并分析了今年落粒多,出的麦苗多的原因有收获过迟,小麦穗粒数多,千粒重高... 小麦收获过晚,在田间易落粒,麦田土壤墒情好,麦田中脱落的麦粒也随之出苗生长。作者通过统计小麦收获后麦田的出麦苗数,进一步估算了麦田脱落的麦粒数和产量损失,并分析了今年落粒多,出的麦苗多的原因有收获过迟,小麦穗粒数多,千粒重高,小穗籽粒多等,而收获过迟是主要原因,并提出了相应的对策措施。 展开更多
关键词 小麦迟收 田间落粒 适时收割
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农作物增产的新型调节剂——云大—120
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作者 吴珍泉 《福建农业》 1999年第8期17-17,共1页
近几年来,一种新型高效植物生长调节剂——云大—120,在各种作物上使用,效果十分明显。使用云大—120有以下几个特点: 一是使用浓度极低 一般在0.01—0.02ppm之间,比其它植物生长调节剂低几千至几万倍,一般的调节剂如比久(1000—4000ppm... 近几年来,一种新型高效植物生长调节剂——云大—120,在各种作物上使用,效果十分明显。使用云大—120有以下几个特点: 一是使用浓度极低 一般在0.01—0.02ppm之间,比其它植物生长调节剂低几千至几万倍,一般的调节剂如比久(1000—4000ppm)、赤霉素(10—300ppm)、多效唑(100—300ppm)等使用浓度都较高。 展开更多
关键词 云大—120 植物生长调节剂 农作物 使用浓度 比久 叶片品质 新型高效 赤霉素 迟收 草霉
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批评与要求(三则)
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《人民论坛》 1996年第6期64-64,共1页
贵刊寄发的各期杂志,一般都能在当月收到,不过有时也出现迟收的现象,希望能缩短我们收发之间的距离,加快投送时间。 山西阳泉建筑二公司 马彦奇 当我收到每期杂志时,看到信封书写的比较工整,但有时笔下也有误,写错姓名。
关键词 投送时间 山西阳泉 刊物价格 贵州六盘水 迟收 信封 姓名 无变化 告示 年度
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远征
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作者 海鸥 《天风》 北大核心 2001年第4期49-49,共1页
每天,我早早起航,夜晚迟迟收帆。 每天,我不顾风拦雨挡,毅然固执远征。 每天,我努力避礁而行,竭力搏击远方。 但请你相信,这不是因为我有许多载不动的愁。
关键词 迟收 无措 传福音 闲游 持守 热汗 图外 心志 轻声 海鸥
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Lazy loading algorithm for traffic assignment of road networks under fixed charge condition
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作者 赵金宝 邓卫 《Journal of Southeast University(English Edition)》 EI CAS 2011年第2期185-187,共3页
The measures of path charge are important considerations in traffic assignment of road networks. Factors, such as travel time, fixed charge and traffic congestion which affect road users' choices of trip paths, are a... The measures of path charge are important considerations in traffic assignment of road networks. Factors, such as travel time, fixed charge and traffic congestion which affect road users' choices of trip paths, are analyzed. Travelers usually decide their trip paths based on their personal habits, preferences and the information at hand. By considering both deterministic and stochastic factors which affect the value of time (VOT) during the process of path choosing, a variational inequality model is proposed to describe the problem of traffic assignment. A lazy loading algorithm for traffic assignment is designed to solve the proposed model, and the calculation steps are given. Numerical experiment results show that compared with the all-or-nothing assignment, the proposed model and the algorithm can provide more optimal traffic assignments for road networks. The results of this study can be used to optimize traffic planning and management. 展开更多
关键词 traffic assignment road networks fixed charge lazy loading algorithm
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邮寄喜报应注意的几个问题
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作者 赵海林 《国防》 1997年第6期44-44,共1页
编辑同志: 最近,笔者就部分干部、战士或其家长来电话、来信,询问部队寄回的立功喜报或优秀士兵喜报为计么迟迟收不到一事专门做了调查,发现造成这一问题的主要原因是邮寄喜报中存在以下问题:一是寄给的单位不够统一。有的将喜报寄给了... 编辑同志: 最近,笔者就部分干部、战士或其家长来电话、来信,询问部队寄回的立功喜报或优秀士兵喜报为计么迟迟收不到一事专门做了调查,发现造成这一问题的主要原因是邮寄喜报中存在以下问题:一是寄给的单位不够统一。有的将喜报寄给了干部、战士所在地的县(市、区) 展开更多
关键词 喜报 几个问题 战士 民政部门 部队 询问部 迟收 同名同姓 士兵 家庭
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Effects of Nitrogen Fertilization on the Growth and N Uptake of Late-sowing Winter Oilseed Rape (Brassica napus L.) 被引量:1
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作者 程博 晁赢 +2 位作者 马霓 张春雷 李光明 《Agricultural Science & Technology》 CAS 2012年第6期1282-1286,共5页
[Objective] The aim of this work was to analyze the N fertilization on the vegetative growth and N uptake of different winter rapeseed varieties at wintering stage. [Method] In two consecutive years (2009-2011), two... [Objective] The aim of this work was to analyze the N fertilization on the vegetative growth and N uptake of different winter rapeseed varieties at wintering stage. [Method] In two consecutive years (2009-2011), two winter rapeseed varieties (B. napus L.), an early maturity variety Zhongyou 116 (ZY116) and a middle-late application maturity variety Zhongyouza 12 (ZYZ12) were employed. Field experiments with different N levels (0, 90, 180, 270, 360 kg N/hm 2 ) were designed. At the wintering stage, the dry matter weight, the nitrogen content and concentration of plants, leaf nitrate reductase activity (NRA) and seed yields were investigated. [Result] The shoot dry matter of ZY116 increased rapidly when N rate ranged from 0 to 180 kg/hm 2 , and it raised slightly when N rate ranged from 180 to 360 kg/hm 2 . The shoot dry matter of ZYZ12 were changed in a single peak curve; the peak of shoot dry matter appeared at 270 kg N/hm 2 . The N concentration and N content in shoot and root increased rapidly when the N rate changed from 90 to 180 kg/hm 2 . Moreover, the N concentration and N content root of in ZYZ12 were much higher than that of ZY116. Present study revealed that the changed trend of leaf nitrate reductase activities (NRA) were significantly increased at the N rate of 180 kg/hm 2 in ZY116 and ZYZ12 compared with the N rate of 90 kg/hm 2 in two years. [Conclusion] Optimal nitrogen application significantly increased the dry weights and N uptake at wintering stage as well as increasing the yield of winter oilseed rape. 展开更多
关键词 Late-sowing Winter oilseed rape (B. napus L.) Dry matter weight Nitrogen uptake Nitrate reductase activity (NRA)
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蔬菜新品种介绍
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《山西农业(致富科技版)》 1994年第3期44-45,共2页
激63—2特长豆角结荚性能好,豆角长60~80cm,最长达1m,典型的6~8根达500g,肉厚质细籽少而小,迟收3~5天不易老化。粗纤维少,品味鲜美。商品市场竞争力强。4年试种亩产均超过4000kg。
关键词 新品种介绍 蔬菜 长豆角 萝卜 德日 肉质根 结荚性 生食 圆柱形 迟收
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Low latency systolic multipliers for finite field GF(2m) based on irreducible polynomials
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作者 谢佳峰 贺建军 桂卫华 《Journal of Central South University》 SCIE EI CAS 2012年第5期1283-1289,共7页
Systolic implementation of multiplication over GF(2m) is usually very efficient in area-time complexity,but its latency is usually very large.Thus,two low latency systolic multipliers over GF(2m) based on general irre... Systolic implementation of multiplication over GF(2m) is usually very efficient in area-time complexity,but its latency is usually very large.Thus,two low latency systolic multipliers over GF(2m) based on general irreducible polynomials and irreducible pentanomials are presented.First,a signal flow graph(SFG) is used to represent the algorithm for multiplication over GF(2m).Then,the two low latency systolic structures for multiplications over GF(2m) based on general irreducible polynomials and pentanomials are presented from the SFG by suitable cut-set retiming,respectively.Analysis indicates that the proposed two low latency designs involve at least one-third less area-delay product when compared with the existing designs,To the authors' knowledge,the time-complexity of the structures is the lowest found in literature for systolic GF(2m) multipliers based on general irreducible polynomials and pentanomials.The proposed low latency designs are regular and modular,and therefore they are suitable for many time critical applications. 展开更多
关键词 finite field finite field multiplication systolic structure low latency POLYNOMIALS
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Efficient Temporal Difference Learning with Adaptive λ
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作者 毕金波 吴沧浦 《Journal of Beijing Institute of Technology》 EI CAS 1999年第3期251-257,共7页
Aim To find a more efficient learning method based on temporal difference learning for delayed reinforcement learning tasks. Methods A kind of Q learning algorithm based on truncated TD( λ ) with adaptive scheme... Aim To find a more efficient learning method based on temporal difference learning for delayed reinforcement learning tasks. Methods A kind of Q learning algorithm based on truncated TD( λ ) with adaptive schemes of λ value selection addressed to absorbing Markov decision processes was presented and implemented on computers. Results and Conclusion Simulations on the shortest path searching problems show that using adaptive λ in the Q learning based on TTD( λ ) can speed up its convergence. 展开更多
关键词 dynamic programming delayed reinforcement learning absorbing Markov decision processes temporal difference learning Q learning
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A Note on "Global Exponential Convergence Analysis of Hopfield Neural Networks with Continuously Distributed Delays"
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作者 CHANG Da-Wei 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第6期1143-1144,共2页
In this note, we would like to point out that (i) of Corollary 1 given by Zhang et al. (cf Commun. Theor. Phys. 39 (2003) 381) is incorrect in general.
关键词 Hopfield neural networks distributed delays equilibrium point globally exponential stability
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Control of stochastic spike motion in an excitable system via recycled noise 被引量:1
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作者 MA Juan GAO QingYu 《Science China Chemistry》 SCIE EI CAS 2011年第9期1504-1509,共6页
The control effect of recycled noise,generated by the superposition of a primary Gaussian noise source and a secondary source with a constant delay,has been studied in an excitable FitzHugh-Nagumo system.We mainly foc... The control effect of recycled noise,generated by the superposition of a primary Gaussian noise source and a secondary source with a constant delay,has been studied in an excitable FitzHugh-Nagumo system.We mainly focus on the performance of noise-induced spike and coherence resonance in a parameter region sub-threshold to supercritical Hopf bifurcation.For fixed noise intensity,simulations show that the coherence(quantitatively measured by R,which is defined as the mean value of the spike interval time T normalized to its mean square root) and the emission velocity of the noise-induced spikes exhibit damped oscillations with the variation of delay time,demonstrating a new kind of multi-resonance phenomenon.Furthermore,the optimal delay times for resonance and the fast emission velocity are related to the inherent frequency of the system.It seems that there are some synchronization effects between the dynamic character of the system and the delay time of recycled noise.Our results give clear information about how one can control the coherence and emission velocity of the noise-induced spike in a rather effective way,by deliberately adjusting the delay time and the fraction of the secondary noise. 展开更多
关键词 stochastic spike excitable recycled noise coherent resonance
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GLOBAL DYNAMICS OF A DELAYED HIV-1 INFECTION MODEL WITH ABSORPTION AND SATURATION INFECTION 被引量:2
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作者 RUI XU 《International Journal of Biomathematics》 2012年第3期191-203,共13页
In this paper, an HIV-1 infection model with absorption, saturation infection and an intracellular delay accounting for the time between viral entry into a target cell and the production of new virus particles is inve... In this paper, an HIV-1 infection model with absorption, saturation infection and an intracellular delay accounting for the time between viral entry into a target cell and the production of new virus particles is investigated. By analyzing the characteristic equations, the local stability of an infection-free equilibrium and a chronic-infection equilibrium of the model is established. By using suitable Lyapunov functionals and LaSalle's invariance principle, it is proved that if the basic reproduction ratio is less than unity, the infection-free equilibrium is globally asymptotically stable; and if the basic reproduction ratio is greater than unity, sufficient condition is derived for the global stability of the chronic-infection equilibrium. 展开更多
关键词 HIV-1 infection ABSORPTION intracellular delay global stability LaSalle's invariance principle.
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Stability of planar waves in reaction-diffusion system 被引量:1
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作者 LU GuangYing WANG MingXin 《Science China Mathematics》 SCIE 2011年第7期1403-1419,共17页
This paper is concerned with the asymptotic stability of planar waves in reaction-diffusion system on Rn, where n 2. Under initial perturbation that decays at space infinity, the perturbed solution converges to planar... This paper is concerned with the asymptotic stability of planar waves in reaction-diffusion system on Rn, where n 2. Under initial perturbation that decays at space infinity, the perturbed solution converges to planar waves as t →∞. The convergence is uniform in Rn. Moreover, the stability of planar waves in reaction-diffusion equations with nonlocal delays is also established by transforming the delayed equations into a non-delayed reaction-diffusion system. 展开更多
关键词 traveling wave fronts STABILITY sup-sub solution reaction-diffusion system
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