准的
- 与 准的 相关的网络例句 [注:此内容来源于网络,仅供参考]
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The current study presents a new clinical technology to detect the stability of dental implant precissively by using natural frequency detection methodology. The study also designs and sets up a compact dental implant stability detector for verifying the theoretical prediction and its usefulness.
本研究利用自然频率检测法设计稳固度检测仪,并配合理论模拟与实际临床需求,加以修正改良,期能得到更精准、更敏锐的稳固度检测值,以便对植体临床手术提供最佳辅助诊断工具。
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The theory of accretion disks are important for many astrophysical phenomena, including Quasars, active galatic nucleic, X-ray binary stars, and young stellar objects. The most important branch of accretion djsk theory is the stability properties of djsks. It is widely considered that the luminosity variations of various astronomical objects are associated with the instability of accretion disk. The viscosity plays an important role in the accretion disk theory, and magnetic field exists commonly in astronomical phenomena. A more realistic analysis of the stabihty of the accretion disk should include both the radjal and azimuthal perturbations because of the strong shear of viscous flow.In this paper, according to the luminosity Variations of Various astronomical objects, we study the radial-azimuthal instability of an isothermal with magnetic field. We find that the radial and azimuthal fields B〓,B〓 are mainly responsible for enhancing the instability of the magneto-acoustic modes and non-axisymmetric modes,and that pulsational oscillations are larger in the radial than in the Z direction. The model may be useful in explaining the periodic light variation of FU orionis and. T Tauri stars.
在许多天体物理现象中,例如活动星系核,X-射线双星和年青的恒星理论中,吸积盘理论起着重要的作用,而吸积盘理论中的一个重要分支是吸积盘的不稳定性理论,普遍认为活动天体的周期,准周期光变现象与吸积盘的不稳定性有关,在吸积盘理论中,粘滞起着重要的作用,而磁场是天体物理中普遍存在的现象,对于几何薄吸积盘不稳定性分析,由于强剪切流的缘故,应该包括径向和环向扰动两个方面,本文结合天体物理中的各种周期,准周期光变现象,研究了含磁场的等温薄吸积盘的径向-环向振荡不稳定性,结果表明:磁场的径向和环向分量对磁声模和非轴对称模的不稳定性的增加起着主要的作用,且径向振荡大于轴向振荡,所得结果有利于解释FU Orionis和T Tauri Stars的周期光变现象。
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Embedding the gradient direction search and new kinds of evaluation functions into the Genetic Algorithm, a special hybrid Genetic Algorithm with mutation along the weighted gradient direction to solve non-linear programming problems is developed. Then in Chapt 4, a type of nonlinear programming problems with fuzzy objective and fuzzy resources constraints is discussed, in which the objective is ill-defined and the resources possess two different types of fuzzy resources, i. e., tolerance and imprecision. By way of description and formulation of fuzzy objective and fuzzy resources, the problem with fuzzy objective and two different types of fuzzy resources is modelled into a fuzzy nonlinear programming model FO/RNLP and interpreted as three equivalent alternative crisp model to reflect the variety of the environment and the subjective and preference of the decision maker .
本文首先针对遗传算法在求解非线性规划问题中存在的问题,首次提出非可行点/染色体的主导准可行方向,准可行方向,及非可行点属于可行域的可行度等新概念,借助于模糊思想,提出了描述和度量非可行染色体的新方法;通过嵌入非可行染色体的信息于评价函数中,提出了三种新的评价非可行染色体的评价函数;把传统的启发式方法-梯度方向搜索和新的评价函数嵌入到遗传算法中,提出了一种沿加权梯度方向变异的新型混合式遗传算法;第四章针对生产实际中非清晰定义的模糊目标和两种类型的模糊资源,建立了一类连续型模糊目标/资源约束非线性规划问题的模型FO/RNLP。
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First, some seismotectonic belts in southeast and northeast Qinghai-Tibet Plateau which have similar geodynamic background are selected.
本文从地震地质学角度出发,充分利用地震学和岩石力学等学科中的相关研究理论和方法,将地震活动与具体的地震构造相结合,探讨了包含多个孕震区或断裂带的大陆板内地区的地震复发规律,提出了大陆板内地震的准周期丛集复发模式,并系统、全面的研究和讨论了不同断裂之间的相互作用及其对活动断裂地震危险性的影响,从机理上揭示了大陆板内地震准周期丛集复发行为的内在物理基础。
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The quasi-perpendicular collisionless shock consists of foot, ramp and a series of overshoots and undershoots, after travelling back upstream for a short distance, the reflected protons gyrate back into the downstream where an temperature anisotropy is formed due to an anisotropy of velocity distribution, then excite Alfvén ion cyclotron waves and mirror waves that dissipate the kinetic energy into heat; At quasi-parallel collisionless shocks, the reflected protons can travel far upstream, and lead to the generation of ion beam instabilities which excite large-amplitude right-hand polarized ultralow-frequency resonant waves whose frequencies are are about〓 These waves are convected back downstream by solar wind and gradually merge to form the downstream state, in the meantime new waves are generated continuously in the upstream, this process where ULF waves are generated and merge into downstream state is cyclical.
准垂直无碰撞激波系由根部、斜坡区以及一系列的低冲和过插组成,被激波反射的质子向激波上游运动很短的距离就在回旋作用下再次向下游运动,和激波发生相互作用以后进入激波的下游,在激波的下游引起质子速度分布的各向异性,进而引起激波下游温度的各向异性,激发起Alfvén离子回旋波和镜波,将激波上游的动能耗散成激波下游的热能;在准平行无碰撞激波(θ〓=10°)情况下,这部分质子能向激波上游运动很大一段距离,并在激波的上游激发起束流不稳定性,引起大振幅的低频波动。
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In one embodiment of the present invention, the optical fingerprint sensor includes:(1) a light source on a PCB assembly,(2) a diffuser that receives light from the light source,(3) a right angle prism that receives light from the diffuser,(4) a collimating lens that receives light from the prism,(5) a first mirror that receives light from the collimating lens,(6) a second mirror that receives light from the first mirror,(7) a third mirror that receives light from the second mirror,(8) an imaging lens that receives light from the third mirror, and (9) an image sensor on the same PCB assembly as the light source that receives light from the imaging lens.
在本发明的实例中,该光学指纹传感器包括有:①一个装在印刷电路板上的光源;②一个散射镜接收从光源发出的光;③一个直角棱镜接收从散射镜出来的光;④一个准直透镜接收从棱镜出来的光;⑤第一块镜子接收从准直透镜出来的光;⑥第二块镜子接收从第一块镜子出来的光;⑦第三块镜子接收从第二块镜子出来的光;⑧一块成像镜接收从第三块镜子出来的光;⑨一个与光源安装在同一块印刷电路板上的图像传感器接收从成像镜出来的光。
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Reefs, reef-mounds and lime mud mounds are all carbonate buildups, and the reefs and banks are important targets for petroleum exploration The reefs, banks and mounds should be divided from each other not only in theory, but also in exploration practice, because of so many differences in sedimentary compositions, fabrics, environments, distribution in time and space, and the characteristics of petroleum geology If the original reef or bank itself was fine reservoir rocks, then it would become a better reservoir after the reservoirconstructive diagenesis The formation of a high quality carbonate reservoir is controlled by two factors: the sedimentary microfacies and the reservoirconstructive diagenesis The first is the basis for the formation of a high quality reservoir, and with the high energy reefbank facies as the best; the latter includes the cataclasis, the dolomitization and the karstification The dolomitization and karstification are the best for the formation of a high quality reservoir The karstification has the widest distribution, profoundest effect, and plays a vital role in the high quality reservoir forming The karst types are quite rich in the limestone reef or bank reservoir, including synsedimentary karst, penesedimentary karst, supergene karst and hydrothermal karst, and so does the dolomitization reef or bank reservoir The formation mechanism of synsedimentary karst and penesedimentary karst is related to the short time exposing and leaching of the cyclical highfrequency shallowupward sequence when the reefs or banks are forming The supergene karst is controlled by the exposing and leaching of tertiary cyclic sequence type I interface after the reefs or banks forming Thus, there developed a great deal of secondary corrosion pores, corrosion fractures and huge caves besides some original pores remained in the reef and bank reservoir Scarcely there are any original effective pores in reefmounds and lime mud mounds, especially in senkes among mounds, but secondary pores could be formed by karstification, and there would likely develop source rocks with high organic abundance
礁、礁丘、丘同属碳酸盐建隆,礁、滩是重要勘探目的层。但各自在沉积组分、组构、环境和时空分布,以及油气地质条件上迥然不同,因而无论从理论还是勘探实践上,都有必要将其各成体系划分开来。礁滩自身为好储集岩,当建设性成岩作用叠加后可形成好的储层。碳酸盐岩优质储层形成,主要受沉积微相与建设性成岩作用两大因素控制。前者是基础,并以高能的礁滩相带为最好;后者主要包括破裂、白云石化和溶蚀三大类,并以白云石化或溶蚀为最优,其中的溶蚀分布最广泛、影响最深刻而对优质储层形成起决定性作用。礁滩储层中的古岩溶类型最为丰富多彩,包括同生期、准同生期、表生期和埋藏期热流体岩溶的所有类型,白云岩化礁滩体也不例外。其中,同生准同生期岩溶的形成机制与礁滩沉积时高频层序旋回向上变浅序列的短暂暴露淋溶有关,表生期岩溶则受控于礁滩沉积后三级层序旋回Ⅰ型界面的暴露淋溶。由此,导致礁滩储层中除了可以也是唯一保存原生孔隙外,还发育了次生溶蚀孔洞缝和大型溶洞。礁丘、灰泥丘尤其是丘间洼地中发育高有机质丰度烃源岩;它们自身没有有效的原生孔隙,但岩溶作用可以形成次生孔隙。
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D models are the most widely spread in the world of turbo-machinery for its simplicity, but they are indeed purely empirical correlations which not only fail to provide detailed information inside one or more components, but also require significant effort to recreate themselves if engine operating conditions or component representations change; quasi 3-D models have been the workhorses for compressor and turbine design for many years, and the primary benefit of using quasi 3-D system models is to facilitate the design and detail analysis of a particular component across the range of possible boundary conditions; Full 3-D models are gradually replacing quasi 3-D ones by virtue of requiring no exit flow angle model and loss model and being capable of predicting secondary flow in cascade.
零维模型由于使用时简单易行,因此在涡轮发动机的仿真中得到广泛应用,但零维模型作为纯粹的经验关系式无法反映部件内部的流动细节,并且一旦部件有少许改动则新特性的建立耗费巨大;准三维模型由于能够详细地提供部件内部的流动情况,方便设计而成为涡轮和压气机设计的主要工具;全三维数学模型正逐步取代准三维模型在涡轮设计中的主导作用,同后者相比前者能够预测叶轮机械内的二次流动,在粘性流计算时不需要气流角和损失的经验公式,因此拥有巨大的发展前景。
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The contents of this dissertation are involved in studies on quasi steady-state condition of a slow speed-varying rotor system, gain-scheduling control of a quasi steady-state rotor active balancing system, adaptive control of active balancing for a fast speed-varying rotor with actuator time delay and adaptive control of active balancing for a fast speed-varying rotor with actuator saturation. The rotors to be studied include a Jeffcott rotor, a Jeffcott rotor with anisotropic bearings, a flexible rotor with single collocated balancing plane (actuator plane and measuring plane are almost the same one) and a flexible rotor with multiple collocated balancing planes.
研究的内容涉及慢变速转子的准稳态条件、变速准稳态转子主动平衡系统的增益调度控制、带作动器时迟的快变速转子主动平衡系统的自适应控制与带作动器饱和的快变速转子主动平衡系统的自适应控制,转子类型包括Jeffcott转子、轴承各向异性的Jeffcott转子、单并置平衡平面(作动器和测量平面几乎在同一个平面)的柔性转子和多并置平衡平面的柔性转子。
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When it is under certain perturbation, a quasi-elliptic response with transmission zeros to improve the transition can be obtained using the transmission zero technique given in the dissertation. Further, a multi-mode resonator composed of a half wavelength resonator loaded with two shunt series LC circuit is also investigated intensive.
本文提出了一种新型准集总元件谐振器,它既具有结构紧凑的优点,又能够引入传输零点构成准椭圆特性响应;本文也提出了一种由半波长传输线加入微扰构成的双模谐振器,并对它的传输零点技术做了全面系统的研究,这种双模谐振器相比传统的环形双模谐振器有更加紧凑的尺寸;本文提出了一种由半波长传输线加载并联串联LC电路构成的多模谐振器并对其在宽带滤波器的应用进行了研究;论文对一种复合谐振器及其在双通带滤波器设计中的应用进行了研究。
- 推荐网络例句
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She gently rebuff ed him, but agreed that they could be friends
她婉言拒绝了,但同意作为朋友相处。
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If in the penal farm, you were sure to be criticized.
要是在劳改农场,你等着挨绳子吧!
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Several theories about reigniting and extinguishing of the arc have been refered.
本文综合考虑了几种电弧重燃和熄灭理论。