在讨论中
- 与 在讨论中 相关的网络例句 [注:此内容来源于网络,仅供参考]
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To resolve the algorithm of the chromatic number of a graph,a special method is adopt to remember the coloring process of graph,and the method does different jobs for four given cases during the coloring process.The adjacent strong edge chromatic number of join graph of star and path is obtained.
为了解决图的邻强边染色问题中一个图的色数算法问题,通过特别的方法来记图的染色过程,同时分4种情况讨论了星和路联图的邻强边染色问题,指出在染色过程中给定的4种情况的染色方法各不相同,并通过对图的着色得到了星和路联图的邻强边色数。
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Developments on arid climate numerical simulations and experiments were introduced in this paper, and surface albedo, soil humidity and parameters of vegetation and their effects on climate were summarized.
介绍了近年来国内外干旱气候数值模拟和试验的研究与进展,总结和评述了陆面过程中地表反照率、土壤湿度、植被状况的参数化和对气候的影响,讨论和阐述陆面过程在气候模拟中的重要性。
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ABSTRACT Aiming at problems of trans-vector controller in a vehicle-carried induction motor such as variable rotor and stator resistance following motor temperature, and their inductance varying with flux saturation degrees. Firstly, CSI and VSI are introduced, for CSI, it can hold the advantages both FOC and DTC using stator flux directional, PI parameter and simulation are also introduced. Secondly, equations of IM in the synchronous rotary frame and its static counterpart, as figuring in the saturation condition of magnetic field, are dealt in this paper and the simulation results are presented. Thereafter, the parameter designing of PI trans-vector controller is processed, which features the non-linear model. In practical realization, as neglecting the dynamical change of motor inductance, this paper employs online modification of inductance parameters, according to the flux saturation, then transforms the non-linear equations into linear ones, and so compacts the structure of controller. Thirdly, in view of the maximum torque output is extraordinary requisite when Electrical Vehicle start up, accelerate, and overtake, this paper issues the maximum torque when both inverter and battery capacity is corporeally definite. Fourthly, on-line differentiating and analyzing both rotor's time constants and its flux by using the expanding order reduction and discrete Kalman filter equation are fathomed, in order to realize high-performance trans-vector algorithm, and also the simulation results are presented. Fifthly, the close-loop regenerative brake system, when the EV's torque is set constant, is deduced; at the same time, unification of electric drive model and brake model is executed. Combined with maximum charge current demands, the mathematical model for online yielding torque as a demand.
本论文针对车载异步电机在矢量控制器所遇到的问题:定转子电阻随温度变化及随电机饱和程度变化的转子电感及定子电感而影响电机调速性能提出一套完整的解决方案:分析了电流型逆变器和电压型逆变器在实现矢量控制时控制器参数的计算,分析出对于电流型逆变器在采用定子磁场定向时,其性能同时具有矢量控制和直接转矩控制两者的优势,并对电压型逆变器在转子磁场定向下的模型进行了仿真研究;建立异步电机非线性模型,推导出考虑磁饱和时异步电机在同步旋转坐标系及静止坐标系下的方程,并做出了仿真结果,建立异步电机在非线性模型下的矢量控制调节器的PI参数设计,在实际应用中,若忽略电机电感的动态变化,可以根据当前的磁路饱和状态而在线修正电感参数,从而将非线性方程线性化,降低控制器的复杂度;考虑到电动汽车在起动和加速超车时需要电机有最大转矩输出,本文讨论在逆变器容量一定和电池供电能力有限的情况下电机最大转矩输出问题;推导了异步电机扩展降阶、离散卡尔曼滤波方程在线辨识转子时间常数和转子磁通,用于实现高性能的矢量控制算法,并给出了仿真结果;推导出了电动汽车恒转矩给定的闭环回馈制动系统,实现了电动控制模型和制动模型的统一,而且结合铅酸电池最大充电电流的要求,为制动转矩在线给定建立了数学模型;设计了基于双DSP系统的高性能矢量控制器软硬件框图,并以大量实验数据说明矢量控制在电动汽车应用的实际应用状况。
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According to the energy conservation theory, BOM and CSIM4 were coupled. The BOM has no treatment on transmission solar radiation, which is of great importance when the model is adapted to Arctic Ocean. So the treatment was introduced to BOM. Through numerical test on different lead albedos, it was found that sea ice thickness is not so sensitive to lead albedo, which may be contribute to the lead occupies little ratio within multiyear sea ice pack. The reason of summer over-melt of arctic sea ice is the NCEP reanalysis downward solar radiation being larger than its reality. Then the arctic sea ice climate variability was simulated. Results showed that: simulated ice thickness change is in accord with the submarine investigated mean sea-ice draft changes. Simulated annually maximum ice thickness along the Eurasian continental oceans are closely related to the observed ones. The long-term mean simulated ice motion has the same features of the SSM/I derived ice motion. Sea ice extents in differential sub-regions have same trends comparing to the satellite passive-microwave data derived ones. Simulated ice concentration is closely related to the observed in the Arctic sub-regions. Sea ice flux through the Fram Strait involves ice concentration, motion and thickness. It is a composite criterion for sea ice model evaluation. The simulated ice area and volume export through the strait accord with the satellite derived or statistically reconstructed ones.(5) The simulated ice thickness climate variability and mean sea surface current of the coupled model were analyzed, results showed: the total ice volume in the Arctic Ocean has a significant decreasing trend. The volume variability is of a 10-year timescale oscillation, with two major periods of 12-13a and 18-20a. Mean ice thickness in the arctic sub-seas has different tendencies. It has an increasing trend in the Barents-Kara Sea and Baffin Bay-Labrador Sea, and decreasing in the others. The characteristic time scale of 7-10a wherein the river discharges leads the Fram Strait ice volume export is about the period that river water takes to be conveyed across the Arctic Ocean.(6) Using the simulated ice distribution in the Arctic Ocean and China precipitation, air temperature and SST in tropical key regions, the climate teleconnection were studied. Result showed: When the mean sea ice thickness is large in the central Arctic Ocean and Chukchi-Beaufort Sea , and small in the Barents-Kara Sea and Baffin Bay-Labrador Sea , the precipitation in South China, Tibetan Plateau, and the north part of Northeastern China are always smaller than normal, and v. v. When the mean ice thickness is small in CA, BC, East Siberian Sea and Greenland-Iceland-Norwegian Sea , and large in BL, The air temperature in north-eastern China, the southern of Tibetan Plateau, and Hainan Island, are always lower than normal, and v. v. In addition, when the sea ice is thick in BC and BL, the SST is larger in the middle and eastern Pacific Ocean, and is smaller in the tropical Southeastern Indian Ocean.
由于BOM没有考虑透射太阳辐射的物理过程,研究表明透射太阳辐射对北冰洋的能量收支起到重要作用,因此在BOM模式中引入了对透射太阳辐射的处理;通过对不同水道反照率的数值试验表明海冰厚度对水道反照率的敏感性不强,可能与海冰区水道面积占的比率很小有关;而模式模拟的北极海冰夏季&过度融化&主要源于NCEP再分析资料提供了偏大的太阳短波辐射;对北极海冰的气候变率进行了模拟研究,结果表明:模拟的海冰厚度变化与潜艇探测的海冰吃深度变化具有一致性;模拟和观测的亚欧大陆沿海的年内最大海冰厚度有很好的相关;模拟的海冰移速与长期平均的卫星反演的海冰移速具有相同的速度分布特征;模拟的各个海区海冰面积的变化趋势与卫星反演资料分析的结果基本一致;模拟与观测的主要海洋分区的海冰密集度具有很好的相关:弗瑞姆海峡的海冰体积和面积的输送涉及到海冰密集度、厚度和移动速度,是判断模式模拟能力的一个综合的指标,模式模拟的结果与卫星反演或重建的面积输送、体积输送具有很好的一致性;(5)分析了模拟的北极海冰厚度的气候变率及气候平均表层海流场,结果表明:北极海冰的总体积有显著减少的趋势,北极海冰总体积的变化具有10a际尺度振荡的特点,存在18-20a和12-13a两个主周期;北极海冰的平均厚度在各个海区的变化趋势不同,在巴伦支—喀拉海和巴芬湾—拉布拉多海地区海冰厚度有显著的增加趋势,而其它海区存在减少的趋势;通过对模拟的气候平均表层海流的分析表明,北极河流流量超前弗瑞姆海峡海冰流量7-10年的特征时间尺度与表层海流的气候分布存在着必然联系:(6)利用模拟结果以及中国降水、气温和热带关键区SST资料,讨论了北极各海区海冰平均厚度与中国降水、气温以及热带关键区SST的关系,结果表明:在北极中心海区和楚科奇—波弗特海海冰厚度偏大,在巴伦支—喀拉海以及巴芬湾—拉布拉多海海冰厚度偏小,则中国降水在华南地区、青藏高原和东北北部降水偏少,反之相反;在北极中心海区、东西伯利亚海、楚科奇—波弗特海以及格陵兰海海冰厚度偏小,在巴芬湾—拉布拉多海海冰厚度偏大,则在中国东北地区、高原南部地区和海南岛附近气温偏低,反之相反;另外,北极楚科奇—波弗特海和巴芬湾—拉布拉多海海冰厚度偏大时,在热带中东太平洋海温偏高,而在热带东南印度洋海温偏低。
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This paper elucidates the necessity of introducing differential geometry in the quantitative study of structural geology and discusses its applications in the quantitative study of structural geology and relevant numerical calculation method.
中文摘要:阐述了在构造地质学定量研究中引入微分几何学的必要性,并讨论了在地质构造定量研究中的具体应用及相关的数值计算方法。
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This papersummarized the changes and change mech...
本文综合论述了脂类物质在火腿加工过程中所发生的变化及变化机制,讨论了这些变化在火腿风味形成中的作用。
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| The culmination of decades of research on humanized mice is leading to advances in our understanding of human haematopoiesis, innate and adaptive immunity, autoimmunity, infectious diseases, cancer biology and regenerative medicine. In this Review, we discuss the development of these new generations of humanized mice, how they will facilitate translational research in several biomedical disciplines and approaches to overcome the remaining limitations of these models.
对人化小鼠的几十年的研究,使我们对人血细胞生成,固有免疫,获得性免疫,自身免疫,感染性疾病,癌症生物学和再生医学有了进一步的理解,在这篇综述中我们讨论了人化小鼠新世代的发育,它们怎样在若干生物医学学科中促进translational research的发展,和克服这些模型局限性的方法。
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The second section introduces their uses in the Present Perfect Tense and in the Continuous Tenses, with senten- ces involving "till" as the focus of discussion, In the third section the stress is put on analyzing the typical wrong sentences written by the chinese beginners of English, foll...
第二部分介绍它们在现在完成时和进行时态中,及在带有till句子中的用法;并以此为讨论中心。第三部分着重分析中国学生典型错误并提出一些改正的方法,所附例句均摘自一些中外英语书刊,以表作者客观的看法。
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Based on the idea of type systems, this paper reengineers a new set of type expressions and a type system for machine code of Intel/x86s infrastructure Although machine language program is a binary untyped code, types of its registers and memory exist implicitly in semantics of instructions The type inferring algorithm built on type systems can statically infer safety of the machine code The machine language discussed includes some of important characters, such as jumps, function call, return, and so on, and shows that the approach can be applied to type checking for low level code of other infrastructures
根据类型系统思想,为Intel/x86体系结构的机器语言重新定义了类型表达式并建立一套类型系统机器语言代码虽然是一种无类型的二进制编码,但其类型信息被隐含在指令的操作语义中,利用建立在类型系统基础之上的类型推理算法可以静态地推理机器代码的安全性由于所讨论的机器语言包含了跳转、函数调用和返回等主要指令,因此,这种静态检查方法可广泛应用于其他体系结构的低级语言代码的检查中
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Here again is the old, much discussed, problem of determining the velocity in one c.s. if it is already known in another.
这里又是前面那个老的、讨论了很多次的问题,即假使知道了一样东西在一个坐标系中的速度,如何决定它在另一个坐标系中的速度。
- 推荐网络例句
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I didn't watch TV last night, because it .
昨晚我没有看电视,因为电视机坏了。
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Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.
今年以来,在北京的很多小区里,电梯液晶电视被撤了下来。
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I'm running my simile to an extreme.
我比喻得过头了。