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41.
英语幽默语的语义基础特征及功能 总被引:1,自引:0,他引:1
杜亚静 《信阳农业高等专科学校学报》2007,17(4):112-114
从语义看,幽默语只有与其他语言形式、具体的语境相结合,才能诠释其幽默。歧义是产生幽默的常用手段,比喻、反语、双关、夸张等手段则是幽默语言中最常用的语言技巧。 相似文献
42.
An analysis of hybrid sterility in rice using a diallel cross of 21 parents involving indica, japonica and wide compatibility varieties 总被引:3,自引:0,他引:3
Summary There is much interest in the inter-varietal fertility of Asian cultivated rice. In this study, we analyzed the fertility of hybrids in a diallel set of 210 crosses involving 21 parents representing a broad range of the cultivated rice germplasm including landraces, primitive cultivars, modern elite cultivars and parents of hybrid rice. The materials were also carefully selected with respect to indica-japonica classification including typical indica/japonica, more or less intermediate and wide compatibility varieties. The level of hybrid fertility varied widely among the crosses from almost completely sterile to fully fertile. In general, hybrid fertility of intra-subspecific crosses, i.e., indica by indica (I×I) and japonica by japonica (J×J), is much higher than inter-subspecific crosses (I×J or J×I). The fertility varied widely in hybrids involving wide compatibility varieties and also in inter-subspecific crosses not involving wide compatibility varieties. An analysis of variance showed that both the main effects of indica and japonica parents and the interaction between the parents are highly significant in determining hybrid fertility. We speculate that, in addition to wide compatibility, the overall genetic difference between the indica and japonica parents, that may involve a series of minor mutations, play an important role in determining the hybrid fertility. There are also genes of sizable effect that influence fertility in hybrids resulting from specific combinations of the parents.Abbreviations I×I
indica by indica cross
- I×J
indica by japonica cross
- J×I
japonica by indica cross
- J×J
japonica by japonica cross
- WCV
wide compatibility variety 相似文献
43.
Nehemia Anthony Mashiringwani Kingstone Mashingaidze Josephine Kangai Klaus Olsen 《Euphytica》1994,76(1-2):33-44
Summary Grain filling rate in wheat (Triticum aestivum L. emend. Thell.) positively influences grain yield under a wide range of conditions. The effective utilization of this trait in breeding depends on an understanding of its genetic control. A study was, therefore, conducted to determine the genetic basis of grain filling rate in six crosses of wheat. Higher order genic interactions and/or linkage were important in the genetic regulation of grain filling rate (GFR) in the majority of crosses. Additive ([d]) and dominance ([h]) gene effects were important in the control of GFR in main ears (ME) and whole plant ears (WPE). Additive and additive × additive epistatic effects were the most important in the genetic control of GFR in last ears (LE). Location effects on genetic effects for GFR were significant (P < 0.05) in all ear types of some crosses except in ME. Genotype × environment interaction effects were important (P < 0.001) in LE and WPE.It was concluded that the inheritance of GFR is complex and is dependent on ear type. Breeding procedures that facilitate the exploitation of non-additive and additive gene effects were recommended for the genetic improvement of grain filling rate of wheat. 相似文献
44.
The time-frequency coupling relation between useful non-stationary components and noises bring great difficulties to the realization of de-noising for non-stationary signals,which can not be solved by classic de-noising method in time or frequency domain. The principles of short time Fourier transform(STFT),Wigner-Ville transform,Chirplet adaptive decomposition are analyzed,and then a novel de-noising method for non-stationary based on joint time-frequency distribution is proposed. In this method,the analyzed signal WVD is seen as the combination of auto-WVD and cross-term WVD. Firstly,STFT energy spectrum of the analyzed signal is used as template to cross-correlate with its corresponding WVD in order to obtain the satisfactory time-frequency distribution with high time-frequency resolution and without cross-term interferences. Secondly,the useful components are decomposed as Chirplet function using the two-dimension least square fitting method,and then are extracted out to reconstruct for noise suppression. Finally,the computer simulation results verify the effectiveness of this proposed method. Its application in gearbox fault diagnosis indicates that with the method the extracted cycle of the gearbox vibration impulses has a good consistency with the corresponding fault frequency. 相似文献
45.
北京地区高产小麦冠层形成和结构及其生理基础的研究 总被引:12,自引:0,他引:12
1980-1989年,以改善北京地区高产小麦产量潜力为目标,对冠层形成和结构以及与高产有关的几个生理问题进行了系统研究。首先确定了选用中间类型叶型的品种、在20cm行距和基本苗15-20万/亩对产量最有利的基础上,提出了一整套包括形态和生理在内的冠层性状指标,为亩产450kg水平的小麦确定了一个框架结构和形成模式。还研究了叶面积指数变化与光透射、生育阶段持续期与粒数和粒重、育性与脱落酸水平变化等之间的关系,高温和水分胁迫的影响,以及不同衰老类型在衰老过程中的形态和生理变化。为制定育种目标和方案、高产栽培措施,提供了生理方面的依据。最后对北京地区高产小麦品种的叶型和株型、粒数和粒重、源和库在决定产量上的相对重要性等问题进行了讨论。本研究在生理与育种、栽培等学科结合的研究上取得了有益的进展。 相似文献
46.
针对目前RBF神经网络训练算法存在的问题,提出了一种模拟人类学习方式的自动调整隐层节点数的在线训练方法,对其理论依据进行了分析,并用实例对其进行了验证。结果表明,此种学习方法速度快、拟合精度高、新旧知识均可记忆,克服了以往算法的不足,具有很大的实用性。 相似文献
47.
论艺术设计基础素描新方法 总被引:1,自引:0,他引:1
在中国艺术设计中传统素描训练偏重于绘画技法的传授,技法的明暗写实素描为主,方法较单一,已不能适应当今艺术设计对人材个性的培养要求,应积极改革借鉴当今国际先进的素描方法及经验.运用现代绘画手段,构建起适应现代艺术特别是艺术设计的现代素描理论体系,本文以全新的视角论述了,素描形象思维的丰富性及素描技法的多元性。文中基于世界范围内艺术与设计的历史演变,基于对视觉思维的整体观照和科学研究,就素描与构成、画法系统等视知觉研究主要问题进行了深入的比较研究,如传统素描与新素描的比较,通过一系列专题及相关练习整合视觉训练课程,为设计基础素描改革提供了新方法、新思路。 相似文献
48.
根据各个教学实验室承担的实验项目,以及基础与提高、近期与中期、国产与进口、室内和室外并举的原则,以30人为一个教学班,其实验室装备标准为:总计仪器设备519台件套,总金额约113万元,人均占有3.76万元;其中室内部分为424台件套,金额约80.5万元,占总金额的7I%,人均占有2.68万元;而教学用、教学科研兼用.科研用的比例为6:2:2。 相似文献
49.
以郑州商品交易所绿豆期货为例,通过价格走势、不同交割月期货价格比较、期货价格与现货价格对比和期货价格周期性模拟等分析,探讨了衣产品期货价格的变化及波动规律。 相似文献
50.
针对CAGD中散乱数据光顺拟合的一般模型的求解问题,采用罚函数方法处理几何约束。根据最优性条件,将反映曲面光顺性的泛函极小化问题,离散化为曲面参数域网格点上的九点差分格式。得到了关于拟合曲面在网格点上函数值的线性方程组,并证明了该线性方程组的系数矩阵对称正定的性质.保证了采用超松弛法求解线性方程组的收敛性。为了验证所提出方法的有效性,对空间散乱分布的14个数据点,当模型参数取不同值时。分别进行了拟合。试验结果表明,用超松弛法能够简单快速实现散乱数据点的光顺拟合。 相似文献