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31.
Qing-Huo Liu Anderson B. Weng Cho Chew 《Geoscience and Remote Sensing, IEEE Transactions on》1994,32(3):494-498
The authors formulate and implement a numerical mode-matching (NMM) method to model electrode-type resistivity tools in invaded thin beds. The authors derive the low-frequency approximation of the Maxwell's equations to obtain the partial differential equation for the potential field. The new NMM program is validated by comparing the numerical results with those obtained from other dc programs. It is found that this new program is much faster than the program using the finite-element method (FEM), and hence is useful for routine interpretation of resistivity logs and for inversion 相似文献
32.
Cho Younghee; Luce R. Duncan; von Winterfeldt Detlof 《Canadian Metallurgical Quarterly》1994,20(5):931
A rank- and sign-dependent utility theory is based on an operation of joint receipt of 2 independent gambles and 3 assumptions regarding the operation (R. D. Luce, 1992). The authors tested these 3 assumptions (i.e., segregation, duplex decomposition, and the additivity of certainty equivalents over joint receipt) using both judged and choice certainty equivalents (CEs). Median choice CEs provided support for both segregation and duplex decomposition but little support for additivity in gains or in losses, whereas median judged CEs also failed to support segregation. The latter failure appears to result from some Ss misunderstanding the instructions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
33.
A new controller for a digital audio amplifier with bit stream input is proposed. The proposed controller has excellent features such as wide error correction range and no limitation on the modulation index. The controller is implemented in the half-bridge class-D amplifier and performance is verified through experiments. 相似文献
34.
Han-Sam Cho Hyun-Kyo Jung 《Energy Conversion, IEEE Transaction on》2002,17(4):492-499
The force equation of a synchronous permanent-magnet planar motor (SPMPM) was investigated. The flux density distribution of a two-dimensional (2-D) magnet array for a SPMPM was obtained by solving the equations of the scalar magnetic potential. The expressions of the force and back-EMF constant were derived and examined. Using these expressions, the conditions for normal operation of the SPMPM were found and the optimal design was determined in order to maximize the force of the SPMPM. 相似文献
35.
A new high-slew-rate CMOS buffer amplifier consuming a very small quiescent current is proposed. This buffer amplifier recursively copies the output driving current and increases the tail current of the input differential pair during slewing. Since the proposed buffer has a possible slew rate higher than 10 V//spl mu/s for a load capacitance of 1 nF almost independently of static currents as low as 1 /spl mu/A, this buffer amplifier is promising for column driver ICs of flat panel displays that require low static power consumption, high current driving capabilities, and small silicon areas. 相似文献
36.
The law of mixtures applied to the plastic deformation of two- phase alloys of coarse microstructures 总被引:3,自引:0,他引:3
The theory of the mechanical law of mixtures is reviewed and applied to the partition of stress and of strain in two-phase
alloys. It is shown that the modified law of mixtures, based on averagein situ stress and strain, is valid for small deformations and is compatible with strengthening theories based on continuum and dislocation
mechanics. The plastic deformation behavior of two representative two-phase alloys,i.e., a spheroidized high carbon steel and a duplex stainless steel, was studied by taking into account the mutual interactions
between phases. The law of mixtures and dispersion strengthening theory were used to evaluate the strength contribution of
each phase. 相似文献
37.
38.
We propose an asymmetric integral imaging method to adjust the resolution and depth of a three‐dimensional image. Our method is obtained by use of two lenticular sheets with different pitches fabricated under the same F/#. The asymmetric integral imaging is the generalized version of integral imaging, including both conventional integral imaging and one‐dimensional integral imaging. We present experimental results to test and verify the performance of our method computationally. 相似文献
39.
Experimental investigation of natural convection from a horizontal ice surface melting in pure water
Byung-Ha Kim Seung-Hwan Cho Kap-Jong Riu 《Journal of Mechanical Science and Technology》1991,5(2):93-103
A study on natural convection from a horizontal ice surface melting in pure water was conducted experimentally for the ambient
water temperature from 2▿C to 10°C. Natural convection flow around upward-or downward-facing horizontal ice plate was divided
into three regions according to the temperature variation of ambient water. The flow patterns of three regions were no flow,
two-dimensional steady laminar flow and unsteady flow. Mean Nusselt number for the upward-facing surface had its maximum value
at about 3°C of ambient water temperature. However, in the case of the downward-facing surface it increased as the ambient
water temperature increased. 相似文献
40.
The reliability and the solderability of thin small outline package (TSOP) are significantly affected by the warpage that is generated after epoxy molding compound (EMC) molding process. This warpage problem mainly results from the mismatch of material properties such as Young's modulus, Poisson's ratio and coefficient of thermal expansion (CTE) and the geometric structure of each component for TSOP. The optimization of both material properties and geometric structures using the numerical analysis is necessary to reduce the warpage of TSOP. However, there are still some limitations for the numerical analysis to obtain proper results consistent with the practical warpage values. In this paper, the numerical analysis is performed under the assumption of elastic behavior for EMC. Furthermore, to solve the limitations, the material properties at the molding temperature and the degree of reaction rate at the end of the molding process of EMC are considered together for the analysis. This numerical analysis gives the higher warpage values than the measured ones, and is applicable to the practical design of the reliable electronic package. 相似文献