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1.
采用介质镜像格林函数法求解芯片中共面传输线的宽频带特性,得到了4层介质结构的格林函数级数表达式,并采用层次法加快了计算速度。研究了半导体Si衬底共面传输线的频变电容和电导参数,其结果与由全电荷格林函数法得到的结果一致。  相似文献   

2.
本文提出一种用分区许瓦兹变换计算金属屏蔽共面传输线基本传输参量的近似计算方法,其中假设共面传输线的导体带条的厚度为零。应用本文方法得出计算程序和计算数据,设计和制作了包含共面传输线的实际电路,并得到了良好的性能。  相似文献   

3.
采用保角变换和部分电容法,导出了耦合共面波导奇偶模单位长度电容及其特性阻抗的解析表达式。数值结果与利用其他方法分析椭圆耦合带线、三带线耦合共面波导和矩形屏蔽耦合共面波导的结果吻合得较好,表明本方法是可行的。  相似文献   

4.
提出了一种基于微机电系统(MEMS)技术的新颖桥式共面波导(BCPW)结构,采用准静态分析方法对其特征阻抗、导体损耗、介质损耗等基本参数进行了理论计算,并与传统共面波导进行了比较分析.结果表明,新设计具有无辐射损耗、宽阻、低损耗、对加工工艺要求低等优点.  相似文献   

5.
采用镜像法与叠加系数法求解了金属球与无限大导体平板系统的电容.根据数学物理理论,本文通过引入叠加系数Cn,k的方法,在金属球与无限大导体平板系统中配置镜像电荷系列,可以精确确定镜像电荷系列中任意象电荷的位置和电量,并采用计算技术工具软件Matlab进行运算与作图,精确计算系统的电容.这种方法分析过程直观、简捷、计算精度高等特点.  相似文献   

6.
用虚位移法计算静电力可分为两种情况:一种为导体的情况;另一种为为介质的情况.给出了用虚位移法计算静电场中电介质受力与用虚位移法计算静电场中导体受力的关系,从而说明了静电场中电介质受力的本质,阐明了静电场中电介质受力的计算可直接应用静电场中导体受力公式的原因,给出了计算介质受力时可以运用计算导体受力公式的条件,并给出了具体的例子进行说明.使电介质受力的计算变得明白、易懂.  相似文献   

7.
对Ⅲ-Ⅴ族电光晶体GaP和GaAs衬底上的共面波导(CPW)进行直接电光调制测量,得到GaP和GaAs的输入电压与电光调制输出的关系曲线,分析电光调制的输出特性.  相似文献   

8.
提出一种新型高阻硅(电阻率ρ>8kΩ.cm)衬底MOS(metal-oxide-semiconductor)结构的凸起式共面波导。给出了其在50MHz~40GHz频段的插入损耗和回波损耗测试结果,以及在-40V~+40V直流偏压下散射参数的变化。结果表明,随着偏压的变化,回波损耗在Ka波段极值点的频率和幅值均会产生偏移,插入损耗极值点的频率基本没有偏移,只存在幅值偏移。共面波导的损耗偏移与MOS结构的Si-SiO2界面效应有关,在凸起式共面波导损耗的偏压实验中,观察到与传统MOS结构共面波导相反的曲线,并尝试给出了理论解释。该文设计的共面波导在35GHz下实现了小于-0.010dB/mm的损耗,优于Ka频段硅衬底共面波导已报道的结果。  相似文献   

9.
气相法同质外延金刚石单晶薄膜的研究   总被引:1,自引:0,他引:1  
本文以<100>和<111>两种取向的金刚石为衬底,用微波PCVD法进行了同质外延实验,考察了衬底取向,反应气体,碳源浓度等因素对外延层形貌与结构的影响,给出了获得比较理想单晶外延层的实验条件。  相似文献   

10.
用启发式方法给出了FMA的基本思想,并以三维导体目标为例分析了FMA的步骤,也给出了MLFMA的基本思路。然后用该方法计算了导体球的RCS,指出该方法的应用前景。通过分析表明该方法在计算速度和存储要求方面比矩量法有明显优势,适合于在现有计算机条件下求解电大尺寸目标的散射问题。  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.
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.
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   

16.
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   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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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