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1.
工程车辆液压元件工作压力的合理选择与匹配   总被引:7,自引:3,他引:4  
通过理论分析对比及与使用数据相结合的方法,分析研究工程车辆液压元件在其动态波动负荷条件下工作压力参数的合理选择与匹配问题,在保持液压元件高效率,合理寿命与可靠性,合理成本的综合性能要求下,提出了液压元件的压力降额匹配原则与方法,为工程车辆液压元件的合理选用及是供理论依据。  相似文献   

2.
大体砼若合理选择配合比,加强施工中的温度控制,运用合理的施工方法,改善约束条件就能有效控制裂缝产生。  相似文献   

3.
本文从“合理最低评标价法”的概念入手,针对合理最低评标价法的应用认识及保障合理最低评标价法实施的方法做了详细的介绍。我们应该以规范的管理,成熟的思考,健全建筑市场机制,使工程造价控制在相对合理的范围内。  相似文献   

4.
水驱油藏合理水平井段长度的确定方法   总被引:3,自引:0,他引:3  
根据资金平衡原理,运用最优化方法,综合考虑水驱油藏水平井开发的技术指标因素和经济指标因素,建立了确定水驱油藏水平井开发中合理水平段长度的优化模型,提出了一种确定水平井合理水平段长度的工程计算方法。同时,还给出了水平井开发中各项费用及收入的计算方法。根据所介绍的方法,在微机上研制和开发了水平井合理水平段长度的优化计算软件。运用该方法对某海上油田进行了计算,与数值模拟计算结果对比表明,该计算方法可应用于水平井开发的优化设计。  相似文献   

5.
在隧道规划和设计阶段要预防可能的病害.危害、进行合理设计;在隧道施工阶段要采用合理的施工工艺、方法、措施和材料以保证施工质量。在隧道运营阶段要及时检查、发现病害,分析病害成因,采用合理的整治设计和施工方法。  相似文献   

6.
在项目建设各阶段中进行工程造价全过程控制采用科学的估算方法和合理的管理措施,把建设工程造价的发生控制在合理的范围和核定的限额以内,使投资控制目标能够实现,以求合理使用人力,物力和财力,取得较好投资效益目的.  相似文献   

7.
介绍了“三量”合理可采期的计算方法,并利用该方法评价了煤峪口矿“三量”的采掘接替状况,确立了该矿的“三量”合理可采期。  相似文献   

8.
老年人肺部感染为临床最常见的感染性疾病,要彻底治愈,不但要合理选用抗生素药物,而且要合理选择抗生素药的给药方法,还要注意营养支持疗法。  相似文献   

9.
本文从合理避税的定义、意义和特征出发,详细的描述了企业合理避税的依据以及其在中小企业中的应用,并就我国开发企业常用的一些避税方法进行了简要的举例分析,探讨企业如何合理避税,利用各种手段提高综合收益,促进国民经济的良性发展。  相似文献   

10.
刘威麟 《特区科技》2010,(12):25-31
价钱如果经过修饰,可营造出“合理”的错觉,让消费者觉得合理而掏钱。但合理的价格不如“低价”。有没有商人可以进一步地运用某种方法,明明没有折价,却营造出“便宜”的感觉呢?最简单的方法,就是将一件卖1000元的衣服拉高到1万元,然后挂个“一折大甩卖”的标签,但这叫“作假”,不堪称“策略”。  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.
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   

13.
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   

14.
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   

15.
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   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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