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1.
算术运算式波兰式、逆波兰式的转换   总被引:2,自引:0,他引:2  
算术运算式可以表示成中序式、波兰式和逆波兰式,而在编译过程中一般采用波兰式或逆波兰式。就算术运算式转换成波兰式和逆波兰式的问题,给出了利用栈来实现的C语言算法。  相似文献   

2.
本讨论了从单糖的Fischer式改写成Haworth式的步骤。给出了正确书写Haworth式的简便方法。  相似文献   

3.
西周金文的连动式和兼语式   总被引:1,自引:0,他引:1  
以西周金文为研究对象 ,分析金文的连动式 ,从动词结构之间的语义关系分为表示先后连续发生的动作、表示目的、表示方式等三种类型 ,还分析金文的三重连动式实际上是表面的三连动 ;金文的兼语式的三种结构类型 ,从语义上看 ,其第一项动词全部是使令类 ;另外还分析连动式和兼语式混合套用的复杂谓语 ;试图从连动式和兼语式这一语法现象使西周金文与商代甲骨文的相衔接。  相似文献   

4.
隐喻式和一致式的认知研究   总被引:1,自引:0,他引:1  
隐喻式和一致式是语法隐喻理论中的两个重要概念。系统功能语言学认为,语法隐喻发生在语法层面,是表达相同意义的语法范畴发生了转换。从认知的角度看,语法隐喻反映了经验的重新建构,是人类认识世界的重要机制。隐喻式有助于我们对语篇既定意义的有效识解,有利于认知效果的获得。许多隐喻式相当于认知语言学的原型理论中的"非范畴化"动词,而一致式则相当于原型的最佳代表。  相似文献   

5.
急切式学习策略和懒惰式学习策略有着不同的学习和分类机制.通过分析急切式学习策略下的普通决策树模型和懒惰式学习策略下的懒惰式决策树模型,提出了一种新的决策树分类模型即Semi-LDtree.它生成的决策树的结点,如普通决策树一样,包含单变量分裂,但是叶子结点相当于一个懒惰式决策树分类器.这种分类模型保留了普通决策树良好的可解释性,实验结果表明它提高了分类速度和分类精确度,特别是在大的数据集合上效果更加明显.  相似文献   

6.
本文用较简单的方法推导空间任意力系平衡方程的另外三种形式;四力矩式、五力矩式和六力矩式。  相似文献   

7.
通过理论推导证明:非延迟式AGC压缩参谋 恢复忆少的能力强于延迟式AGC,但反调制失真较为理;而延迟式AGC的过渡过程短于非延迟式AGC,且反调制失真较小;两者抑制干扰脉冲的能力相同。  相似文献   

8.
祝圣远 《科技信息》2013,(4):436-437
本文分析了目前我国热风炉发展的现状:顶燃式热风炉发展迅速,但内燃式热风炉仍数量众多。通过分析传统内燃式热风炉的缺陷及顶燃式热风炉相应的优点,提出了将内燃式热风炉改造为顶燃式热风炉的大体思路,并介绍了某工程内燃式热风炉改造的实例。内燃式热风炉改造为顶燃式热风炉是未来发展的趋势。  相似文献   

9.
朱国俊 《科技信息》2013,(18):15-15
本文简述电子标签拣货的两种方式摘取式和播种式拣货的定义以及电子标签拣货的适用范围,重点介绍了摘取式和播种式拣货的异同点,总结了电子标签拣货的优点。  相似文献   

10.
本文简述电子标签拣货的两种方式摘取式和播种式拣货的定义以及电子标签拣货的适用范围,重点介绍了摘取式和播种式拣货的异同点,总结了电子标签拣货的优点。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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