• 열처리공학회지
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• 제15권2호
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• pp.65-69
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• 2002

$Llo{\rightarrow}Ni_5Al_3$ reordering and related properties in Ni-Al alloys consisting of 64-65at%Ni are characterized by X-ray diffraction, shape memory effect and damping capacity. Formation of $Ni_5Al_3$ takes place by simple ordering of atoms with a continuous increase in c/a ratio. As a result, degradation of shape memory effect and damping capacity is observed after short time annealing at $200-300^{\circ}C$.

• 대한조선학회논문집
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• 제41권5호
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• pp.1-7
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• 2004

The Spar platform with deep draft is characterized as effective structure in extreme wave condition, which has larger natural period than that of waves in sea. In this paper, the time domain simulation of motion responses of Spar with catenary mooring line is presented in irregular waves. The memory effect is modeled by added mass at infinite frequency and convolution integrals in terms of wave damping coefficients. The added mass, wave damping coefficients and wave exciting forces are obtained from three-dimensional panel method in the frequency domain. The motion equations are consisted of forces for inertia, memory effect, hydrostatic restoring, wave exciting and mooring line. The forces of mooring line are modeled as quasi-static catenary cable.

• Computational Structural Engineering : An International Journal
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• 제2권1호
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• pp.43-50
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• 2002

This paper presents a method to predict dynamic responses of floating bodies in the time domain. Because of the frequency-dependence of the radiation wave forces, the memory effect must be taken into account when the responses are evaluated in the time domain. Although the formulations firstly developed by Cummins (1962) have been well-known for this purpose, the effective numerical procedure has not been established yet. This study employs FFT (Fast Fourier Transform) algorithm to evaluate the memory effect function, and the equations of motion of an integro-differential type are solved by Newmark-β method. Numerical examples for a truncated circular cylinder have indicated the effectiveness of the proposed numerical procedure.

• 지식경영연구
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• 제6권2호
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• pp.67-90
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• 2005

Attention has been focused recently on the concept of shared cognition which encompasses the notion that effective team members hold knowledge that is overlapping and complementary with teammates. This shared cognition is expected to improve team effectiveness. In contrast to the continued efforts in developing theoretical approach of shared cognition, empirical studies are meager. Thus, we conducted an empirical study to investigate the role of shared cognition on team effectiveness. This study classifies shared cognition into two types, team mental model and transactive memory system, by shared meaning. A total of 121 new product development teams in the IT industry were surveyed for the data collection. The results of analysis can be summarized as follows: first, team mental model has a positive influence on team performance, team innovative behavior and team learning effect. And the relation with team mental model and team performance is moderated by the similarity of knowledge structure among the expert. Second, transactive memory system has a positive influence on team performance, team innovative behavior and team learning effect.

• Asia Marketing Journal
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• 제17권2호
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• pp.1-13
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• 2015

It is becoming increasingly difficult for advertisers to reach target consumers because memory for an ad is inhibited in the presence of competing ads. While previous studies have focused on ad repetition as a factor that can reduce competitive interference, this study focuses on ad distinctiveness. We compare the effects of ad distinctiveness on recall for the ad and its competing ad in high competitive ad environments with those in relatively low competitive ad environments. Regarding the effect of ad distinctiveness on recall for the focal ad, the results show that when an advertiser makes its ad distinctive, recall for its own ad is enhanced in both high and low competitive ad environments although the positive effect is relatively weak in high competitive environments. The results also show that, regarding the effect of ad distinctiveness on recall for its competing ad, when an advertiser makes its ad distinctive, recall for its competing ad is enhanced in low competitive ad environments rather than in high competitive ad environments.

• Smart Structures and Systems
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• 제16권4호
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• pp.641-665
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• 2015

In this paper, a simple and efficient phenomenological macroscopic one-dimensional model is proposed which is able to simulate main features of shape memory alloys (SMAs) particularly ferro-elasticity effect. The constitutive model is developed within the framework of thermodynamics of irreversible processes to simulate the one-dimensional behavior of SMAs under uniaxial simple tension-compression as well as pure torsion+/- loadings. Various functions including linear, cosine and exponential functions are introduced in a unified framework for the martensite transformation kinetics and an analytical description of constitutive equations is presented. The presented model can be used to reproduce primary aspects of SMAs including transformation/orientation of martensite phase, shape memory effect, pseudo-elasticity and in particular ferro-elasticity. Experimental results available in the open literature for uniaxial tension, torsion and bending tests are simulated to validate the present SMA model in capturing the main mechanical characteristics. Due to simplicity and accuracy, it is expected the present SMA model will be instrumental toward an accurate analysis of SMA components in various engineering structures particularly when the ferro-elasticity is obvious.

• Advances in materials Research
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• 제8권4호
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• pp.337-359
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• 2019

Shape Memory Polymer Composites (SMPC) have gained popularity over the last few decades due to its flexible shape memory behaviour over wide range of strains and temperatures. In this paper, non-linear bending analysis has been carried out for SMPC beam under the application of uniformly distributed transverse load (UDL). Simplified C⁰ continuity Finite Element Method (FEM) based on Higher Order Shear Deformation Theory (HSDT) has been adopted for flexural analysis of SMPC. The numerical solutions are obtained by iterative Newton Raphson method. Material properties of SMPC with Shape Memory Polymer (SMP) as matrix and carbon fibre as reinforcements, have been calculated by theory of volume averaging. Effect of temperature on SMPC has been evaluated for numerous parameters for instance number of layers, aspect ratio, boundary conditions, volume fraction of carbon fiber and laminate stacking orientation. Moreover, deflection profile over unit length and behavior of stresses across thickness are also presented to elaborate the effect of glass transition temperature (T_g). Present study provides detailed explanation on effect of different parameters on the bending of SMPC beam for large strain over a broad span of temperature from 273-373K, which encompasses glass transition region of SMPC.

• JSTS:Journal of Semiconductor Technology and Science
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• 제8권1호
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• pp.46-50
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• 2008

The effect of physicochemical properties of solvents on the microstructure of polyvinyl carbazole (PVK) film for non-volatile polymer memory was investigated. For the solubilization of PVK molecules and the preparation of PVK films, four solvents with different physicochemical properties of the Hildebrand solubility parameter and vapor pressure were considered: chloroform, tetrahydrofuran (THF), 1,1,2,2-tetrachloroethane (TCE), and N,N-dimehtylformamide (DMF). The solubility of PVK molecules in the solvents was observed by ultravioletvisible spectroscopy. PVK molecules were observed to be more soluble in chloroform, with a low Hildebrand solubility parameter, than solvents with higher values. The aggregated size and micro-/nano-topographical properties of PVK films were characterized using optical and atomic force microscopes. The PVK film cast from chloroform exhibited enhanced surface roughness compared to that from TCE and DMF. It was also confirmed that the microstructure of PVK film has an effect on the performance of non-volatile polymer memory.

• Journal of electromagnetic engineering and science
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• 제7권4호
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• pp.147-153
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• 2007

This paper represents an analog predistortion linearizer for the high power amplifier with low memory effect. The high power amplifier is implemented using a 90-W peak envelope power(PEP) LDMOSFET at 2.14-GHz and an envelope short matching topology is applied at the active ports to minimize the memory effect. The analog predistortion circuit comprises the fundamental path and the cuber and quintic generating circuits, whose amplitudes and phases can be controlled independently. The predistortion circuit is tested for two-tone and wide-band code division multiple access(WCDMA) 4FA signals. For the WCDMA signal, the adjacent channel leakage ratios(ACLRs) at 5 MHz offset are improved by 12.4 dB at average output powers of 36 dBm and 42 dBm.

• 셀메드
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• 제2권2호
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• pp.19.1-19.6
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• 2012

$Capparis$ $zeylanica$ Linn. a 'Rasayana' drug is used for its memory enhancing effects in the traditional Ayurvedic system of medicine. The aim of this study was to evaluate acetylcholinesterase (AChE) inhibitory and memory enhancing activities of $Capparis$ $zeylanica$ Linn. The$in-vitro$ and $ex-vivo$ models of AChE inhibitory activity were used along with Morris water maze test to study the effect on memory in rats. The anticholinesterase effect of methanolic and aqueous extracts of $Capparis$ $zeylanica$ was measured by spectrophotometric Ellman method at 0.1, 0.3, 1.0, 3.0, 10 and 30 mg/ml and brain monoamine oxidase (MAO-A and MAO-B) activity was assessed by Naoi's method. The results $in-vitro$ and $ex-vivo$ AChE assay revealed that methanolic and aqueous extracts of $Capparis$ $zeylanica$ inhibit AChE activity, whereas these extracts did not alter MAO activity at any concentration tested as compared to moclobemide and L-deprenyl. The results indicate that $Capparis$ $zeylanica$ improves scopolamine-induced memory deficits through inhibition of AChE activity, and not by direct MAO inhibition.