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1.
对6S模型中的算法进行了探讨,并提出了不同的看法:a.6S模型中将向上辐射强度分解为5个组分是没有必要的,事实上其中有些组分很难计算,其计算结果也不够精确,同时这5个组分之和也并不严格等于总辐射强度;b.6S模型对邻近效应的计算也存在着较大误差;c.一维地-气耦合辐射的数值计算只是一个很简单的问题,宜首选国际辐射传热界发展的离散坐标法来求解;d.宜选用逆向蒙特卡罗法来分析邻近效应.另外,对最近提出的多步法做了进一步扩展,以使其能计算更多的向上辐射强度组分.最后,提出了一种更便于大气订正的向上辐射强度划分方法.  相似文献   

2.
用于卫星遥感大气订正的一种辐射强度算法(Ⅱ)   总被引:1,自引:1,他引:0  
根据辐射的叠加性,提出了一种新方法——多步法来计算向上辐射强度组分.采用了两个测试问题验证多射线法和多步法,并与6S模型的计算结果进行了对比.计算结果表明,一维地-气耦合辐射只是一个十分简单的过程,6S模型中的向上辐射强度的划分显得过于繁琐,也没有必要.  相似文献   

3.
用于卫星遥感大气订正的一种辐射强度算法(Ⅰ)   总被引:3,自引:2,他引:1  
基于改进的微分近似法以及大气辐射DOS ISW算法,提出了用于大气订正的一种简单而精确的计算向上辐射强度的算法——多射线法,即对于沿着每一个投射到遥感器上的方向,分别用几个完全相同的带无穷小加权的离散方向来代表总辐射强度以及程辐射等组分,该算法考虑了地-气交互作用,可计算到任意高的精度,还可同时计算从任意方向投射到空基或地基遥感器上的辐射强度组分.  相似文献   

4.
磁场偏差的存在,严重地影响波荡器的辐射谱.用数值模拟方法计算出场偏差对即将建造的合肥800MeV电子储存环波荡器基波辐射谱及三次和五次谐波辐射谱的影响,并给出了辐射强度随光学相位的变化关系,提出了要得到较好辐射强度的光学相位差的极限值.  相似文献   

5.
提出了一种新的数值方法,使得逆向蒙特卡罗法不但可以计算总辐射强度,还能计算直接强度和介质强度.在此方法的基础上,提出了一种改进的方法:光子分类法,该方法既能更详细地计算辐射强度组分,又能大大减少计算时间;然后比较了新方法和多射线法在计算辐射强度组分时的结果;最后将光子分类法应用于分析卫星遥感大气订正中的邻近效应问题.  相似文献   

6.
用离散坐标法计算卫星遥感成像过程   总被引:1,自引:1,他引:0  
发展了一种既可以计算多维大气辐射,又可同时计算卫星遥感成像的新型方法,其步骤是:首先采用一个常规的离散坐标求积系列计算多维大气辐射场;然后采用DOS ISW计算投射到卫星遥感器镜头上的辐射强度,从而获得遥感器CCD相机靶面上的辐射能分布.给出了一个尝试性的计算示例.  相似文献   

7.
研究了碰撞、辐射、原子和分子的计算模型(CRAM)模拟介质阻挡放电中Ar-Hg等离子体的动态特性.在本模型中,不仅考虑了汞原子内部能级的跃迁,也考虑了准分子的形成过程.从介质阻挡放电等离子体的非平衡特性出发,对等离子体的演化全过程进行了模拟.在发展了一种新的处理电子、离子复合方法的基础上,得到了Ar-Hg等离子体的演化规律.此外,还研究了汞原子的共振辐射及其准分子辐射强度与电源频率和管壁温度的关系.其中,汞原子的共振辐射强度反转的结果是与所报道的实验结果相一致的.  相似文献   

8.
离散辐射强度法计算辐射传热是热流密度法的一种修正方法,它引进了比辐射热流密度更原始的变量即辐射强度。本文采用紊流动量方程、K-ε双方程紊流模型及能量方程相结合的方法对冲击加热炉内温度场进行了数值模拟,其中能量方程的源项辐射传热采用离散辐射强度法计算,为以对流传热为主的综合传热过程提供了一种理论研究途径。  相似文献   

9.
选用一合理的模型,估算了1994年7月发生的彗(SL9)—木相撞辐射引力波的强度和功率.所得结果表明引力辐射强度远低于目前引力波检测装置所达到的灵敏度.计算过程与所得结果富有启发性  相似文献   

10.
分析了高增益砷化镓光导开关中流注(即电流丝)一端不同辐射波长的自发辐射实验现象,导出了不同辐射波长的辐射复合系数之间的关系,拓展了电流丝的自发辐射随电流丝电流变化的数学模型.计算结果表明,丝电流相同时流注自发辐射的其他峰值强度略小于890nm自发辐射强度.  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.
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 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   

15.
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   

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.
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   

18.
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   

19.
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   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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