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1.
利用正交样品函数付氏算法,对一类交流采样原理算法进行了研究,利用二表测量原理得出工程上实现一类交流信号采样的计算方法,给出了采样值矩阵获取方法和CT/PT交流信号调理及滤波电路及实现交流信号采样计算的函数,并用C语言实现了用该方法进行的设计。通过工程证明,利用这各交流信号采样方法并选用小CT/PT进行交流采样的方法精度高,适用于电力系统和其它工业控制系统的交流数据采集。  相似文献   

2.
一类γ射线工业CT系统设计的研究   总被引:1,自引:0,他引:1  
研究了由透射成象的γ射线工业CT的设计原理以及数据采集传输,计算机,自动控制,机械扫视和图象重建等子系统的协调,参数分配和数据校正。  相似文献   

3.
设计完成了二维8×8DCT/IDCT处理器系统。该系统由两个一维DCT/IDCT功能块和一个矩阵转换存储功能构成,采用并行结构,流水线操作。根据分布算法,用存储器查表的方法取代了乘法操作。  相似文献   

4.
比较了国内外CT的计算机体系结构;针对我国首台γ射线工业CT(XN-1300ICT)的计算机体系的可靠性进行了分析;同时从提高可靠度及系统连续运行时间的角度出发,提出了确定计算机体系内备件配置量的方法。  相似文献   

5.
FACTS 技术计算机辅助工程平台   总被引:2,自引:0,他引:2  
介绍了用于柔性交流输电技术(FACTS)装置控制系统设计和运行的计算机辅助工程(CAE)平台。讨论了CAE平台的系统结构、数据流程以及实现的功能。给出了CAE平台的软件和硬件设计方法:软件设计采用Windows95和VisualC++作为工具进行开发,并提供了对硬件系统的接口,因此用户界面友好,使用方便;硬件部分采用工业控制计算机为母机,以DSP为协处理器,易于满足实时控制和提高装置可靠性的要求。CAE平台作为一个一体化的环境,能支持FACTS装置控制器设计的整个生命周期,即理论设计、数字仿真、在线调试、动模实验和实时运行  相似文献   

6.
设计完成了二维8×8DCT/IDCT处理器系统.该系统由两个一维DCT/IDCT功能块和一个矩阵转换存储器功能块构成,采用并行结构,流水线操作.根据分布算法,用存储器查表的方法取代了乘法操作.给出算法、系统框图和时序图,对各个功能块进行了设计.采用Verilog-XL语言编写了程序,完成了对主要功能块的模拟.  相似文献   

7.
为进行石油岩芯驱替机理的深入研究,应用工业CT技术,提出了一种石油岩芯孔隙度及分布CT密度差测量法,并进行了实际测量。  相似文献   

8.
建立了闭式涡轮转盘塔(CTRDC)的传质数学模型-简化的扩散模型,并用数值计算方法求得塔内浓度分布和传质系数Koda。计算结果与实验测定值相当吻合,说明模型能较好地反映CTRDC中的传质状况,可用于CTRDC塔高的设计计算。  相似文献   

9.
研究了在工业计算机断层扫描成象(ICT)中,增强图象的小波方法,与增强前的ICT图象比较,上有噪声低和边缘突出的特点,可滤去ICT图象中的非白噪声,这种方法也可用于医学CT等领域。  相似文献   

10.
在论证了我国首台工业CT的数据采集与传输系统串/并行两种设计方案的可行性基础上,择优选定串行方案设计了该系统。  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.
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.
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.
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   

17.
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   

18.
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   

19.
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   

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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