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151.
Optical measurements of thermal diffusivity of a material   总被引:2,自引:0,他引:2  
The measurement of thermal diffusivity of a material (in particular, a thin film) is important for various reasons, e.g., to predict the heat transfer in the solid subjected to a thermal process, to monitor surface composition or morphology, or to detect invisible subsurface defects like delaminations. This measurement can be done in a noncontact manner using various photothermal methods. Such methods typically involve pulsed heating of the surface by small amounts using a laser source; the decay of the surface temperature after this pulsed photothermal heating is then probed to provide the thermal diffusivity. Various probing methods have been developed in the literature, including the probing of reflection, refraction, and diffraction from the pulsed heated area, infrared thermal radiometry, and surface deformation. This paper provides an overview of such techniques and some examples of their applications.  相似文献   
152.
This paper presents a simple but relatively accurate procedure for the analysis of unbonded prestressed continuous flat slabs. Bi‐circular curves instead of conventional parabolic ones are introduced to obtain the characteristic parameters of the curved tendon profiles. Based on the proposed tendon profile and theory of thin plates, a series of simple formulae are derived to compute the bending moments of flat slabs. The validity of the proposed method is demonstrated by comparing the results with those obtained from finite element analysis. The results of the analysis presented in this paper indicate that the proposed method turns out to be convenient and reasonably accurate in the analysis of prestressed flat slabs. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
153.
154.
Determining contributions of source-monitoring and inhibitory function to age-related forgetting has been an elusive goal for cognitive theorists. Five studies used a verbal working memory paradigm to examine mechanisms accounting for disproportionate retroactive interference (RI) experienced with adult aging. Participants distinguished studied target-word pairs from interfering pairs that were read aloud. Source-monitoring and inhibitory task components varied through manipulations of response requirements. RI effects were primarily due to source-monitoring failures rather than to inhibitory failures. Removing both source and inhibitory components eliminated age differences in RI. When source monitoring was emphasized, RI continued to be observed in all age groups but disproportionately for older adults. Process dissociation analyses of memory found recollection decreases and familiarity increases consistent with source failures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
155.
The present paper describes an assumed strain finite element model with six degrees of freedom per node designed for geometrically non-linear shell analysis. An important feature of the present paper is the discussion on the spurious kinematic modes and the assumed strain field in the geometrically non-linear setting. The kinematics of deformation is described by using vector components in contrast to the conventional formulation which requires the use of trigonometric functions of rotational angles. Accordingly, converged solutions can be obtained for load or displacement increments that are much larger than possible with the conventional formulation with rotational angles. In addition, a detailed study of the spurious kinematic modes and the choice of assumed strain field reveals that the same assumed strain field can be used for both geometrically linear and non-linear cases to alleviate element locking while maintaining kinematic stability. It is strongly recommended that the element models, described in the present paper, be used instead of the conventional shell element models that employ rotational angles.  相似文献   
156.
In the last three years or so we at Enterprise Platforms Group at Intel Corporation have been applying formal methods to various problems that arose during the process of defining platform architectures for Intel's processor families. In this paper we give an overview of some of the problems we have worked on, the results we have obtained, and the lessons we have learned. The last topic is addressed mainly from the perspective of platform architects.  相似文献   
157.
The secondary effluent from municipal plants in Korea generally represents higher BOD with lower SS. Therefore, more soluble forms of organics and NH4-N need to be removed to improve its effluent for reuse. In this study reuse possibility of secondary effluent and CSO (combined sewer overflow) using BAF (biological aerated filter) was evaluated. The tertiary application with 1.2 h EBCT, SS, BOD and COD showed stable concentrations less than 1.3, 1.3 and 6.2 mg/L, respectively. Nitrogen could be nitrified even at 7 degrees suggesting BAF can be used for a water reuse method as well as an effective add-on facility in cold regions. However, BAF was not stable with CSO application at increased flow rates suggesting CSO must be equalised prior to application. Disinfection was necessary even during normal weather conditions.  相似文献   
158.
Yeom  H.J. Park  Y.C. Chang  Y.H. 《Electronics letters》2007,43(25):1410-1411
Presented is an eigen filter to remove autogenic electrical stimulation artefacts and M-waves while preserving the volitional electromyographic signal. The optimality of the eigen filter is shown, along with simulated and measured data to indicate its superior performance over conventional prediction error filters.  相似文献   
159.
This paper presents a new approach for using stereo and motion correspondences to solve the problem of tracking multiple independently moving features. In this approach, quantitative relational structure (QRS) is proposed as a framework for the integration of stereo–motion correspondences. The similarity function, tightly coupled to stereo and motion cues, is constructed on QRS, and then energy function E2 consisting of the similarity function is defined. The tracking problem can be converted into the maximization problem of the energy function E2. The stereo and motion correspondences that maximize E2 are recovered by applying an extended graduated assignment algorithm. The relaxation labeling method is also presented for the comparison with the proposed method. Experimental results are presented to illustrate the performance of the proposed method.  相似文献   
160.
There is a plethora of techniques to measure the adhesion strength of metal/polymer interfaces. However, the practical adhesion strength, which is the work done in separating the film from the substrate (or one film from another), is very sensitive to the test methods and the mechanical effects, such as the residual stress, thickness and mechanical properties of the layers, strain rate, and phase angle. Deriving intrinsic-adhesion properties of the interfaces, which are independent of such parameters, from the practical adhesion-strength measurements is a formidable task. In the present work, data from the three commonly used adhesion tests; pull-out, 90°-peel, and T-peel tests are compared with the intrinsic-adhesion properties of the interface, such as the interface-fracture toughness or the interface-fracture energy, and their implications are discussed. Material systems analyzed were Cu-based lead frame/epoxy-molding compound (EMC) and Cu/Cr/polyimide.  相似文献   
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