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分析了五强溪水电站左岸船闸边坡岩体结构特征,介绍了基于工程地质力学综合集成方法论所形成的综合治理的方法。提出了在阻断或削弱引起边坡变形的外在因素的基础上,通过工程处理与加固,以达到提高其边坡稳定性之目的的五强溪边坡治理模式。作者还以大量的监测资料对该边坡综合治理的效果作了论证。该边坡治理设计思路和采用的加固技术,可望为同类条件下的边坡设计和施工提供借鉴。 相似文献
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We present here tunable lasing from holographic distributed feedback (DFB) resonator of electroluminescent conjugated polymer waveguide. Tunable holographic lasing from 560 to 590 nm was simply achieved by rotating a Lloyd-mirror waveguide configuration. Lasing performance for the first order (m = 1) is superior to that for the second order (m = 2). Threshold for lasing for m = 1 is in the range of 25 to 50 μJ/cm2/pulse, which is close to that for amplified spontaneous emission (ASE), and that for m = 2 is larger than 104 μJ/cm2/pulse. For m = 1, slope efficiency of 7.3% including ASE in addition to lasing emission was measured, whereas for m = 2 slope efficiency between 0.1 and 0.2% was measured. 相似文献
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Xintian Wang 《代数通讯》2017,45(11):4809-4816
Stability conditions play an important role in the study of representations of a quiver. In the present paper, we study semistable representations of quivers. In particular, we describe the slopes of semistable representations of a tame quiver for a fixed stability condition. 相似文献
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坡地植物反射高光谱影响因子分析 总被引:1,自引:0,他引:1
在坡地植物遥感监测过程中,很多相关因素的变化会对监测结果产生不容忽视的影响。本文对坡地植物的坡度、坡向、探测天顶角以及不同植物类型等因素进行了分析。为了加强理论探讨,研究在实验室条件下进行,并对均匀坡坡地植物进行了模拟。通过试验发现这些因素对植物高光谱遥感都有影响。当仅坡度变化时,在0°~36°坡度范围内,坡地植物反射比随坡度增大而先增大后减小;当仅探测天顶角变化时,随着探测天顶角的增大,坡地植物在可见光波段光谱特征变化并不明显,在近红外波段反射比逐渐减小;当仅坡向变化时,坡面越转向迎光方向,坡地植物反射比越大,且以入射面与坡面的垂直交线为轴,轴两侧坡向植物叶片反射比基本成对称分布;另外,不同植物类型其光谱曲线有较大差异,即植物类型的差异同样会对坡地植物高光谱遥感产生影响。本研究突破了传统遥感垂直收集数据的局限,利用多角度、高光谱信息进行坡地植物光谱特性分析。坡地植物的高光谱遥感研究对定量遥感的发展有一定的理论意义,同时对植物遥感监测有一定的应用价值。 相似文献
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设计了基于数字信号处理技术的混合式长时间积分器,利用DSP计算出一定时间t内积分器的漂移斜率,从而计算出漂移量,进行扣除,达到减少漂移的目的。EAST装置上的实验结果证明,积分器解决了零点漂移的问题,适合于托卡马克放电实验中诊断信号的测量。 相似文献
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The physics of dry friction is often modelled by assuming that static and kinetic frictional forces can be represented by a pair of coefficients usually referred to as μs and μk, respectively. In this paper we re-examine this discontinuous dichotomy and relate it quantitatively to the more general, and smooth, framework of rate-and-state friction. This is important because it enables us to link the ideas behind the widely used static and dynamic coefficients to the more complex concepts that lie behind the rate-and-state framework. Further, we introduce a generic framework for rate-and-state friction that unifies different approaches found in the literature.We consider specific dynamical models for the motion of a rigid block sliding on an inclined surface. In the Coulomb model with constant dynamic friction coefficient, sliding at constant velocity is not possible. In the rate-and-state formalism steady sliding states exist, and analysing their existence and stability enables us to show that the static friction coefficient μs should be interpreted as the local maximum at very small slip rates of the steady state rate-and-state friction law.Next, we revisit the often-cited experiments of Rabinowicz (J. Appl. Phys., 22:1373–1379, 1951). Rabinowicz further developed the idea of static and kinetic friction by proposing that the friction coefficient maintains its higher and static value μs over a persistence length before dropping to the value μk. We show that there is a natural identification of the persistence length with the distance that the block slips as measured along the stable manifold of the saddle point equilibrium in the phase space of the rate-and-state dynamics. This enables us explicitly to define μs in terms of the rate-and-state variables and hence link Rabinowicz's ideas to rate-and-state friction laws.This stable manifold naturally separates two basins of attraction in the phase space: initial conditions in the first one lead to the block eventually stopping, while in the second basin of attraction the sliding motion continues indefinitely. We show that a second definition of μs is possible, compatible with the first one, as the weighted average of the rate-and-state friction coefficient over the time the block is in motion. 相似文献