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131.
笔记本电脑、PDA等便携式产品的音频电路通常工作在一个极为嘈杂的环境.  相似文献   
132.
Whereas psychological assessment remains a critical skill, it can demand considerable time and effort. In fact, it can often feel tedious and even laborious. As a partial outgrowth, short forms in psychological testing are intrinsically appealing. Unfortunately, many concerns can be raised regarding this practice. This article represents a response to A. P. Thompson, S. G. LoBello, L. Atkinson, V. Chisholm, and J. J. Ryan (see record 2004-95164-011) and is intended to strengthen the discussion on this practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
133.
Optical filters are an important building block in the next generation of optical communication systems. Optical networks seem to be headed towards densely packed wavelength-division multiplexing (WDM) systems. These WDM systems require optical filters for the purpose of wavelength selection and switching. Numerous optical filters have been proposed including acousto-optical filters, electro-optical filters, and Fabry-Perots. Acoustically tunable optical filters (ATOFs) are considered promising. ATOFs are not only an important WDM device; they have great potential in many other applications such as optical spectroscopy. The acousto-optic tunable filter has a unique combination of desirable properties. These properties make it a potentially important building block  相似文献   
134.
Here we report for the first time accurate and comprehensive measurements of electrical properties of individual CoPt/Pt multilayer nanowires both with periodic and non-periodic layer structures. A remarkably high failure current density of 1.69 × 10(12) A m(-2) for the periodic MNW and a similar 1.76 × 10(12) A m(-2) for the non-homogeneous MNW has been measured. The resistance of both types of multilayer nanowire structures are well fitted by a series resistance model, determining the separate resistance contribution of the component layers and magnetic/nonmagnetic interfaces for a single multilayer nanowire. The field-dependent interface resistance of both samples is calculated, 13.2 Ω for periodic layer structures and 4.84 Ω for non-periodic layer structures. The clear physical picture of the resistance distribution within individual multilayer nanowires is then determined. The accurate electrical testing of magnetic multilayer nanowires provides basic and necessary electrical parameters for their usage as building blocks or interconnects in nanoelectronics and nanosensors.  相似文献   
135.
This is the May 1996 report of a subpanel of the US Department of Energy Fusion Energy Sciences Advisory Committee (FESAC), charged with conducting a review of the progress, priorities and potential near-term contributions of TFTR, DIII-D and Alcator C-MOD (and other facilities as appropriate) as part of the transition to a Fusion Energy Sciences Program and produce an optimum plan for obtaining the most scientific benefit from them.  相似文献   
136.
Uncertainty of Predictions of Embankment Dam Breach Parameters   总被引:3,自引:0,他引:3  
Risk assessment studies considering the failure of embankment dams often require the prediction of basic geometric and temporal parameters of a breach, or the estimation of peak breach outflows. Many of the relations most commonly used to make these predictions were developed from statistical analyses of data collected from historic dam failures. The prediction uncertainties of these methods are widely recognized to be very large, but have never been specifically quantified. This paper presents an analysis of the uncertainty of many of these breach parameter and peak flow prediction methods. Application of the methods and the uncertainty analysis are illustrated through a case study of a risk assessment recently performed by the Bureau of Reclamation for a large embankment dam in North Dakota.  相似文献   
137.
Compound terms play a surprisingly key role in the organization of lexical ontologies. However, their inclusion forces one to address the issues of completeness and consistency that naturally arise from this organizational role. In this paper, we show how creative exploration in the space of literal compounds can reveal not only additional compound terms to systematically balance an ontology, but can also discover new and potentially innovative concepts in their own right.  相似文献   
138.
The outcome of this work is a knowledge-based associate ergonomic tool that assists in determining visibility of stationary small objects critical to the work environment. The Luchlesh and Moss detection solid, a design handbook guideline, accounts for non-search visibility in terms of three fundamental variables — visual angle, brightness and contrast. To reduce the difficulty of using the solid in its current form, this effort first quantified the empirical relationships of the solid. The intelligent system building tool, Exsys, was then employed: (1) to convert the results into rules for a knowledge base, and (2) to generate a tool called the Visual Detectability Analysis Associate. An efficient, convenient and easy to use ergonomic design tool is now available that determines visibility of small stationary objects in work environments where viewing time may be limited, but visual search is not required. In current use by a company to solve visibility problems encountered in system design, the VDAA tool has demonstrated beneficial savings in both time and effort.  相似文献   
139.
Tony Gustafsson 《Automatica》2002,38(3):433-443
Subspace-based system identification is typically based on an estimate of the extended observability matrix. It is thus of great interest to investigate, and also optimize, the estimate of the observability matrix. Of special interest in this paper is the fact that the influence of certain weighting matrices is an unresolved issue in the literature on subspace identification. Here, an asymptotic analysis of the estimated observability matrix is presented. The main result of the analysis is that novel weighting matrices and pre-filters of instrumental variables are derived.  相似文献   
140.
This paper proposes a natural and efficient way to achieve staircase reduction in texture extraction models of image processing. Moreover, we propose a precise framework for this amalgamation. In a sense, we utilize the best of both worlds: (I) the use of higher order derivatives through a variant of the Chambolle–Lions inf convolution energy (an image decomposition model in itself) along with (II) approximations to Meyer’s G and E norms including the H−1 negative norm for ameliorating staircasing in image decomposition and restoration problems.  相似文献   
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