• Journal of information and communication convergence engineering
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• v.9 no.1
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• pp.59-63
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• 2011

Conventional noise reduction filtering schemes realize limited improvements of the peak signal-to-noise ratio (PSNR) in the low-level noisy images. The flatness degree and the edge information are effectively used to estimate the noise volume. We propose a noise estimator for reducing noise in the AWGN (additive white gaussian noise) corrupted images using three intermediate image maps (FGM(flatness gray map), FIM(flatness index map), NEM(noise estimate map)). The proposed noise estimator is fed into the conventional noise reduction filters as a pre-processor. The performance of noise reduction is tested in the various AWGN corrupted images.

• Applied Chemistry for Engineering
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• v.26 no.1
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• pp.99-103
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• 2015

We conducted reduction reactions of graphene oxide (GO) using three selected reductants. The conductivity and solubility of three kinds of the reduced graphene oxides (RGOs) were examined based on the degree of reduction. When the ethylene glycol (EG) was used as a reductant, the reduction reaction did not sufficiently progress and as a result the conductivity of RGOs was observed to be relatively low. For RGOs made by hydrazine (HZ) and thiourea dioxide (TU), we observed no significant differences in the degree of the reduction, conductivity and dispersity in water. However, RGO prepared by TU showed an exceptionally good solubility in N-methylpyrrolidone, and the solution was stable for more than 4 months.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.377-378
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• 2002

In many dynamic systems, unwanted vibrations which may arise during operation of machines are costly in terms of reduction of performance and service life. Sometimes these risky oscillations endanger equipment and personnel. When hydraulic telescopic booms taken large mass are driven at slow speeds between the two pads, unstable oscillations occur through the stick-slip at the sliding parts and become more severe and saw-toothed. This paper supposes few models for the telescopic boom in the multi-degree of freedom system, and attempts a theoretical approach for the numerical analysis in its stick-slip condition, It was verified that this theoretical approach has an effect on estimate of stick-slip in the one-degree as well as multi-degree of freedom system.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.11
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• pp.1541-1543
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• 2013

This paper presents a spherical motor which can control in multi-degree of freedom operation. The spherical motor has been researched by many types of structure. Thhis paper shows a spherical shaped airgap and surfaced permanent magnets. Especially, The motor consists of dual rotor cores. Unlike a cylindrical motor, the spherical motor design can be considered with azimuth direction on spherical coordinates. Therefore the permanent magnet surfaced on the rotor need to be designed optimally in order to generate a sinusoidal magnetic flux density in the airgap. This paper presents results of optimal design for reducing torque ripple of the multi-degree of freedom spherical motor.

• Journal of Information Processing Systems
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• v.16 no.1
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• pp.184-200
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• 2020

Similarity searching is a basic issue in information processing because of the large size of formal contexts and their complicated derivation operators. Recently, some researchers have focused on knowledge reduction methods by using granular computing. In this process, suitable information granules are vital to characterizing the quantities of attributes and objects. To address this problem, a novel approach to obtain an entropy-weighted concept lattice with inclusion degree and similarity distance (ECLisd) has been proposed. The approach aims to compute the combined weights by merging the inclusion degree and entropy degree between two concepts. In addition, another method is utilized to measure the hierarchical distance by considering the different degrees of importance of each attribute. Finally, the rationality of the ECLisd is validated via a comparative analysis.

• Child Health Nursing Research
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• v.10 no.1
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• pp.22-28
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• 2004

Purpose: The purpose of this study was to identify the effect of hand acupuncture on reduction of headache. Method: This study used a quasi-experimental pre-test and post-test design. 45 middle school girls who complained of headache were selected as subjects. The study lasted from November 2002 to June 2003. There were 22 girls in the experimental group while 23 girls were control group; convenience assignment was used. The two groups were homogeneous on characteristics. The experimental group received hand acupuncture. The treatment was to puncture corresponding points (A33, B27, M1, I2) on both the palm and the back of a hand with disposable acupuncture needles, and then remove them after a 20-30 minutes recess during which the subjects reclined on a bed. The data were analyzed using the SPSS PC with Fisher's Exact -test, and Mann Whitney U-test. Result: The results of this study were as follows: 1) In the experimental group, objective pain decreased after hand acupuncture (U= -2.51, p= .01). As for the objective pain degree, a significant reduction in voice change was observed in the experimental groups (U= -2.35, p= .02). Facial expressional changes were observed (U= -1.87, p= .06) and perspiration degree (U= -.99, p= .32) has reduced. However, these differences were not statistically significant between the experimental and control group. 2) Subjective pain degree decreased after hand acupuncture in the experimental as compared to the control group. 3) No statistical significant difference in comfort (U= -.29, p= .78) or distress (U= -1.51, p= .13) between experimental and control group were found. Conclusion: These findings indicate that hand acupuncture is an effective method for reducing headache. Therefore, hand acupuncture can be considered as an independent nursing intervention for headache reduction.

• Advances in concrete construction
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• v.9 no.4
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• pp.413-421
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• 2020

For steel-concrete girders made composite using shear studs, initial damage on studs induced by weld defect, unexpected overloading, fatigue and others might degrade the service performance and even threaten the structural safety. This paper conducted a numerical study to investigate the static behavior of damaged stud shear connectors that were embedded in ultra high performance concrete (UHPC). Parameters included damage degree and damage location. The material nonlinear behavior was characterized by multi-linear stress-strain relationship and damage plasticity model. The results indicated that the shear strength was not sensitive to the damage degree when the damage occurred at 2/3d (d is the stud diameter) from the stud root. An increased stud area would be engaged in resisting shear force as the distance of damage location from stud root increased and the failure section becomes inclined, resulting in a less reduction in the shear strength and shear stiffness. The reduction factor was proposed to consider the degradation of the shear strength of the damaged stud. The reduction factor can be calculated using two approaches: a linear relationship and a square relationship with the damage degree corresponding to the shear strength dominated by the section area and the nominal diameter of the damaged stud. It was found that the proposed method is preferred to predict the shear strength of a stud with initial damage.

• Communications of the Korean Mathematical Society
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• v.23 no.2
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• pp.279-284
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• 2008

In this paper, we present the constrained Jacobi polynomial which is equal to the constrained Chebyshev polynomial up to constant multiplication. For degree n=4, 5, we find the constrained Jacobi polynomial, and for $n{\geq}6$, we present the normalized constrained Jacobi polynomial which is similar to the constrained Chebyshev polynomial.

• Korean Chemical Engineering Research
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• v.55 no.3
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• pp.379-384
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• 2017

An electrochemical reduction of a mixture of NiO and rare earth oxides has been conducted to increase the reduction degree of rare earth oxides. Cyclic voltammetry (CV) measurement was carried out to determine the electrochemical reduction behavior of the mixed oxide in molten LiCl medium. Constant voltage electrolysis was performed with various supplied charges to understand the mechanism of electrochemical reduction of the mixed oxide as a working electrode. After completion of the electrochemical reduction, crystal structure of the reaction intermediates was characterized by using an X-ray diffraction method. The results clearly demonstrate that the rare earth oxide was converted to RE-Ni intermetallics via co-reduction with NiO.

• The Journal of the Acoustical Society of Korea
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• v.20 no.6
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• pp.46-50
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• 2001

This paper proposes a new recognition time reduction algorithm Score-Cache technique, which is applicable to the HMM-base speech recognition system. Score-Cache is a very unique technique that has no other performance degradation and still reduces a lot of search time. Other search reduction techniques have trade-offs with the recognition rate. This technique can be applied to the continuous speech recognition system as well as the isolated word speech recognition system. W9 can get high degree of recognition time reduction by only replacing the score calculating function, not changing my architecture of the system. This technique also can be used with other recognition time reduction algorithms which give more time reduction. We could get 54% of time reduction at best.