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71.
72.
An efficient algorithm detecting the presence of a fetal QRS complex is presented. The proposed fetal QRS detection method computes the averaged magnitude of the difference between the fetal ECG signal and the reference signal to detect the fetal QRS event. The detected fetal QRS complexes are exponentially averaged to generate the template signal which can track the slowly varying shape of the fetal ECG signal. As an effort to obtain improved detection performances, two approaches of normalizing the fetal ECG signal and the template are considered.  相似文献   
73.
Disagreement exists in the literature concerting the activity of NiO in (Ni,Mg)O solid solutions. Ideal behavior, as well as strong positive deviations and strong negative deviations from ideality, has been reported. In the present study, the activity of NiO was determined by electromotive force measurements using the solid-state cell Pt/Ni-NiO/0.92ZrO2-0.08Y2O3/Ni-(Ni,Mg)O/Pt. The compositions studied had NiO mole fractions of 0.1,0.3,0.5,0.7, and 0.9. In agreement with theoretical expectations, the solid solutions exhibited ideal behavior at 882° and 982°C. Possible reasons for the conflicting results in the literature arc presented.  相似文献   
74.
 Experimental studies on the aerodynamic coupling effect on natural frequencies and flutter instability of rotating disks are investigated in this paper. The experiments performed using a vacuum chamber and optical disks give two main results. One is that the aerodynamic effect by surrounding air reduces the natural frequencies and critical speeds of the vibration modes in pre-flutter regions. The other is that the natural frequency of the disk rotating at ambient atmospheric pressure is equal to that in vacuum at the flutter onset speed where the disk experiences aero-induced flutter. In post-flutter regions, the aerodynamic coupling between the disk and surrounding air increases the natural frequencies of the disk. Received: 17 June 2002/Accepted: 7 October 2002 The work was supported by Grant No. R11-1997-042-090001-0 of the Center for Information Storage Devices designated by the Korea Science & Engineering Foundation. Paper presented at the 13th Annual Symposium on Information Storage and Processing Systems, Santa Clara, CA, USA, 17–18 June, 2002  相似文献   
75.
The Error-in-Variables Model (EVM) applies to a large class of problems in parameter estimation in which there is error in all the variables. This property makes it of more general applicability than the widely used technique of ordinary Least Squares. While there is a voluminous literature on EVM there is nothing on a general method for designing experiments when EVM applies. In this paper we present an extension of the concept of D-optimality to provide such a general method. It is illustrated by applying it to the estimation of copolymer reactivity ratios and to fitting an ellipse.  相似文献   
76.
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   
77.
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   
78.
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   
79.
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   
80.
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