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51.
对In(0.2)Ga(0.8)As/GaAs应变多量子阱在77K下的光调制反射谱(PR)和热调制反射谱(TR)进行了实验研究.对PR结果的线形拟合指认了应变多量子阱中子能级的跃迁,并与理论计算结果作了比较.实验对比确认PR中11H、13H等跃迁结构为非耦合态、具有电场调制机构的一阶微商性质.而11L、31H、22H等跃迁结构为阶间耦合态,对这些隧穿耦合的低场调制产生三阶微商特性. 相似文献
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A comparison is made of a differential-competitive-learning (DCL) system with two supervised competitive-learning (SCL) systems for centroid estimation and for phoneme recognition. DCL provides a form of unsupervised adaptive vector quantization. Standard stochastic competitive-learning systems learn only if neurons win a competition for activation induced by randomly sampled patterns. DCL systems learn only if the competing neurons change their competitive signal. Signal-velocity information provides unsupervised local reinforcement during learning. The sign of the neuronal signal derivative rewards winners and punishes losers. Standard competitive learning ignores instantaneous win-rate information. Synaptic fan-in vectors adaptively quantize the randomly sampled pattern space into nearest-neighbor decision classes. More generally, the synaptic-vector distribution estimates the unknown sampled probability density function p( x). Simulations showed that unsupervised DCL-trained synaptic vectors converged to class centroids at least as fast as, and wandered less about these centroids than, SCL-trained synaptic vectors did. Simulations on a small set of English phonemes favored DCL over SCL for classification accuracy. 相似文献
54.
Research in CASE environments has focused on two kinds of integration: tool and object. A higher level of integration, process integration, which represents development activities explicitly in a software process model to guide and coordinate development and to integrate tools and objects, is proposed. Process integration uses software process models (SPMs) a process driver, a tool set, and interfaces for both developers and managers to form the backbone of a process-driven CASE environment. The developer's interface, a working environment that lets developers enact an SPM, and the manager's interface which gives managers and analysts the tools to define, monitor, and control the SPMs that developers are working on concurrently are discussed. The Softman environment experiment, an implementation of process-driven CASE environments with existing CASE environments, is reviewed 相似文献
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混合结构楼房爆破拆除倒塌范围的确定 总被引:2,自引:1,他引:1
通过对混合结构楼房爆破倾倒过程特点的分析,提出了楼房在倾倒过程中的运动计算模型,并应用体积平衡原理,得到这类楼房爆破爆堆参数计算公式,用该公式计算的结果与实例中爆堆实测数据相比较,相对误差不超过11%. 相似文献
57.
The interaction of alkali metal with surfaces has been of great interest to the community of catalysis since alkali metal can play an important role as a promoter. On alkali-doped MoS2, such a promotion effect of alkali metal has been exemplified in the direct synthesis of linear alcohols from CO and H2, where the alkali-doping switches the catalyst selectivity from methanation to alcohol synthesis. This paper reviews recent high-resolution X-ray photoelectron spectroscopy experiments that have provided direct
observation of electron transfer from alkali metals to a model single crystal MoS2 and the capture of the supra-valence electrons in the subsequent oxidation reactions. 相似文献
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Daniel Won‐Kyu Hong Choong Seon Hong 《International Journal of Network Management》2003,13(2):115-127
This paper proposes a high‐performance connection management architecture to design a common QoS framework applied to an ATM network based on the Open Distributed Processing (ODP) concept. We design the QoS framework in accordance from the RM‐ODP information and computational viewpoints. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
60.