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1.
易燃易爆介质防爆抑爆技术研究进展   总被引:8,自引:0,他引:8  
对易燃易爆介质的防爆抑爆技术进行了阐述,指出了目前监测控制技术,惰化技术,爆炸泄放技术的应用特点及技术关键;封闭空间抑爆技术比较成熟,利用传感测控技术,抑制剂技术,抑爆启动技术和阻火隔爆技术较好地解决了封闭空间的防爆抑爆问题,开敞空间抑爆技术虽然利用传感技术,抑制剂技术解决了一些问题,火焰减速灭火机理以及环保型抑制剂的灭火机理仍是目前热门研究课题。  相似文献   

2.
技术进化的数量分析   总被引:1,自引:0,他引:1  
技术进化是技术哲学中的一个重要课题。技术进化实质上就是对其进行描述的标度数量的增长并发生质的提高过程。首先阐述了技术是一种复杂的社会现象,分析了技术进化的历程,给出了技术进化的标度,从量的视角探讨了技术进化的动力模型,同时对技术进化过程中的突变进行了定量分析。为技术进化的数量研究,提供了一条有益的途经。  相似文献   

3.
大规模互联网络的入侵检测   总被引:5,自引:0,他引:5  
介绍了大规模互联网络入侵检测技术的发展现状,对网络入侵检测的体系结构,异常检测技术,响应技术,入侵检测的协同技术,网络基础设施的保护技术等热点问题进行了讨论,指出了该领域的一些发展重点。  相似文献   

4.
组件技术和软件代理技术的发展,对电子商务产生了重大的影响,这里概述了组件技术和软件代理技术的特征,讨论了基于组件技术的C2C电子商务系统框架,着重叙述了软件代理技术在用户个性化信息检索中的应用。  相似文献   

5.
虚拟现实(Vinual Reality,VR)技术作为数字城市的支撑技术之一,对城市规划具有重要意义从虚拟现实的概念出发,论述了虚拟现实的3个基本特征及其技术系统的构成,分析了虚拟现实技术应用于城市规划的优势,介绍了虚拟现实技术在城市规划中的关键技术,并以珠江新城为例,探讨了虚拟现实技术应用于城市规划的实施步骤,最后还针对珠江新城虚拟现实系统进行了评价,同时提出了关于VR技术应用于城市规划的几点不足.  相似文献   

6.
太阳能发电技术综述   总被引:3,自引:0,他引:3  
本文论述了太阳能的利用技术,重点讨论了太阳能的发电技术,综合介绍了太阳能塔热气流发电技术、太阳能热发电技术和太阳光发电等国内外各种太阳能发电技术,并进行了比较。在阐述各种发电技术的理论与优缺点的基础上,对太阳能发电技术的前景做了探讨。同时,也简要地介绍了我国在太阳能发电技术上的发展现状,指出了我国大力开发太阳能发电系统的有利条件和自然空间。  相似文献   

7.
丁东升 《应用科技》2004,31(7):64-65,68
依据微生物吞吐技术机理,结合微生物吞吐技术现场试验及效果,探讨了微生物吞吐技术在外围油田的应用,利用微生物吞吐技术,不仅可以解除堵塞,改善原油性质,还能达到提高原油产量的目的,总结了微生物吞吐技术的适应井况,阐述了微生物吞吐技术在外围油田的应用前景。  相似文献   

8.
随着科学技术的发展,无线通信技术得到了迅速发展,但无线通信技术在发展的过程中也出现了一系列的问题,遇到了很多技术上的阻碍,目前我国正逐渐进入3G时代,无线通信技术在我国得到了快速的发展。本文分析了无线通信技术的各自特点,并对无线通信技术发展趋势做以探讨。  相似文献   

9.
Chiplet(芯粒)技术是近年来兴起的新一代集成电路技术,因其具有提升良率、突破光罩极限、芯片架构灵活、芯片组件技术供应货架化等特点,受到产业界的广泛重视。为进一步推动chiplet技术在中国的发展,梳理了chiplet技术的应用场景,分析了chiplet中的各种核心组件技术,阐述了在chiplet技术开发中可能出现的各种技术挑战,回顾了中国chiplet标准的发展情况,最后针对中国发展chiplet技术提出了建议。  相似文献   

10.
随着计算机技术、网络通信技术的高速发展,实现基于Intemet技术、面向对象技术、数据库技术并且考虑电力市场需求的一体化技术的基础条件已经成熟。本文讨论了在电力市场环境下,实现一体化技术的支撑平台,阐述了系统的软硬件结构和组成,最后讨论了该系统的技术特点。  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.
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.
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   

14.
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   

15.
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   

16.
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   

17.
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   

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.
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   

20.
1 Rise of studies on climate change's effects on biodiversity
Until the 1980s, climate change and biodiversity were studied as two independent disciplines for more than a century. In 1992, the Ecological Society of America's annual report named climate change, biodiversity, and the sustainable ecological system as the three major global environmental issues of the twenty-first century [1].  相似文献   

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