• Journal of Convergence for Information Technology
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• v.11 no.2
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• pp.238-242
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• 2021

The purpose of this study is to maintain healthy hair by treatment. Frequent permutations cause a lot of damage to the ends of the hair, and use permant wave pre- and post-processing agents step by step to protect the damaged ends of the hair. The Ginkgo Biloba Leaf Extract used in this study are effective for anti-bacterial, antioxidant, anti-cancer blood circulation and skin moisturizing. This extract was soaked in 1 perm paper and 2 perm papers and wound, and then the cuticle, tensile strength and wave formation rate were investigated. An average comparison analysis was conducted, and when the ginkgo leaf extract was applied to two perm paper sheets, the permanent hair tip showed the highest hair improvement effect.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.1930-1935
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• 2009

This paper deals with the torque ripple reduction of permanent magnet synchronous motor using harmonic current injection. Torque ripple of electric motor reduces system stability and performances, therefore efforts to reduce torque ripple are exerted in the design process. Torque ripple can be reduced by appropriate pole/slot combination, skew of rotor or stator, design of magnetic circuit, etc. In addition, torque ripple can be also reduced by input voltage and current, and many researches have been conducted to reduce torque ripple for six-step drive. Torque ripple reduction for current vector controlled permanent magnet synchronous motor also have been conducted and verified by investigating back emf wave form. Torque ripple reduction in this paper started from getting torque profile according to input current and electrical angle calculated by FEA, then instantaneous currents at each electrical angles for constant torque are calculated and applied to experiments. Therefore, 0% of torque ripple can be obtained theoretically with harmonic current injection. In order to maximize the effect of torque ripple reduction, a BLDC motor having high harmonic component of back emf is chosen. With sinusoidal current drive, over 100% of torque ripple is obtained initially, then 0.5 % of torque ripple is obtained by FEA using harmonic current injection. The effect is verified by experiment and the presented method can be effectively applicable to Electric Power Steering(EPS).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.1
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• pp.688-695
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• 2017

This paper deals with characteristics analysis of a permanent magnet (PM) linear generator using analytical methods for wave energy harvesting. The wave energy is carried out from the movement of a yo-yo system. A linear generator using permanent magnets to generate a magnetic force itself does not require a separate power supply and has the advantage of simple maintenance. In addition to the use of a rare earth, a permanent magnet having a high-energy density can be miniaturized and lightweight, and can obtain high energy-conversion efficiency. We derived magnetic field solutions produced by the permanent magnet and armature reaction based on 2D polar coordinates and magnetic vector potential. Induced voltage is obtained via arbitrary sinusoidal input. In addition, electrical parameters are obtained, such as back-EMF constant, resistance, and self- and mutual-winding inductances. The space harmonic method used in this paper is confirmed by comparing it with finite element method (FEM) results. These facilitate the characterization of the PM-type linear generator and provide a basis for comparative studies, design optimization, and machine dynamic modeling.

• Textile Coloration and Finishing
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• v.24 no.3
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• pp.213-220
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• 2012

In this study, we investigated the effect of natural vegetable treatment agent on the bleaching and damage of human hair during permanent wave formation. The vegetable treatment agent was prepared by fermenting the mixture of tea leaves (10g), black rice (100g), black bean (100g), corn (100g), malt (50g), and water(500g) at room temperature for 1 week. The degree of bleaching and damage was checked by Munsell value 'L' and morphological changes of hair in FE-SEM. When the hair was bleached, the Munsell value 'L' was almost same regardless of adding the vegetable treatment to the bleaching solution. But when the hair was permanently waved, the curl formation ability was high and the damage was low in the case of adding the vegetable treatment. This means that the vegetable treatment covers the scale of hair and protects the hair from the chemicals.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.1
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• pp.108-115
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• 1995

An efficient model for the dynamic analysis of caisson breakwaters under impulsive wave loadings is presented. The caisson structure is. regarded as a rigid body, and the rubble mound foundation is idealized as virtual added masses, springs, and dampers using the elastic half-space theory. The frequency-dependent hydrodynamic added mass and damping coefficients are considered by using the time memory functions and added mass at infinite frequency. To simulate the permanent sliding phenomenon of the caisson, the horizontal spring is modeled as a nonlinear spring with plastic behaviors. Comparisons with experimental results show that the present model gives fairly good results. Sensitivity analysis is performed for the relevant parameters affecting the dynamic responses of a caisson breakwater. Numerical experiments are also carried out to investigate the applicability to the prediction of permanent sliding distance and critical weight of the caisson.

• Journal of the Korean Applied Science and Technology
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• v.25 no.2
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• pp.137-143
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• 2008

Chemicals for cosmetics, including skin, the skin absorbs some of the research in the field of science or pharmacy recently, about the environment and the health of the heightened interest in skin absorption, and many other human attributes and absorption evaluation studies are underway in various areas. In this study, The effects of commercial permanent wave products to skin which are composed with cysteine and bases using rat. Results are as follows; the content of penetration 4 hours later with steady state and no significant changeable after 20 hours later. In cysteine groups lag time and permeability coefficient of young skin is 3.32hr and $0.102{\mu}g/cm^2{\cdot}hr$, lag time and permeability coefficient of old skin is 4.04hr and $0.106{\mu}g/cm^2{\cdot}hr$. In conclusion of study lag time and permeability coefficient in old skin and wounded skin are faster than healthy skin. We notified that fine rinkle and rash of skin were changeable in the case of treating with permanent wave drugs than normal skin.

• Land and Housing Review
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• v.1 no.1
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• pp.75-82
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• 2010

Urban development is a cause of expansion of impervious area. A permanent storage is operated as a method of reducing runoff of watershed. The purpose of study is to propose reasonable choice of simulation model for rainfall-runoff in the prior review system on disaster effect. First, we indicated problem about concentration time choice in the flood simulation. To test the adequacy of a rainfall-runoff simulation model, We analyzed characteristics of rainfall-runoff about urban and natural watersheds. A simulation model was calibrated with the storm of july 7 to July 9 in 2009. From the result, we proposed that SWMM and kinematic wave method as the flood simulation models for urban and natural watersheds. A simulation model and design method of a permanent storage for flood that is proposed in this study will be useful for practical design of flood simulation. The hydrologic analysis method of the study can be used for capacity evaluation of permanent storage plan.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.856-857
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• 2008

Wave power generation as an environmentally -friendly energy has received the attention. In this paper, therefore, the tubular type Permanent Magnet Linear Synchronous Generator (PMLSG) is proposed for wave power generation. The characteristics of tubular type PMLSG are investigated by analysis using a Finite Element Analysis (FEA). Moreover, the operating performance of generator under no-load and load with variable resistance is examined. And Taguchi method is applied for considering tolerance in manufacture. The results of FEA show that proposed tubular type PMLSG is a useful solution for small-scale wave power generation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.4
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• pp.181-189
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• 2000

A weakly nonlinear mild-slope equation has been derived directly from the continuity equation with the aid of the Galerkin's method. The equation is combined with the momentum equations defined at the mean water level. A single component model has also been obtained in terms of the surface displacement. The linearized form is completely identical with the time-dependent mild-slope equation proposed by Smith and Sprinks(1975). For the verification purposes of the present nonlinear model, the degenerate forms were compared with Airy(1845)'s non-dispersive nonlinear wave equation, classical Boussinesq equation, andsecond¬order permanent Stokes waves. In this study, the present nonlinear wave equations are discretized by the approximate factorization techniques so that a tridiagonal matrix solver is used for each direction. Through the comparison with physical experiments, nonlinear wave model capacity was examined and the overall agreement was obtained.

• Fashion & Textile Research Journal
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• v.11 no.1
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• pp.156-165
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• 2009

The purpose of this study was to compare men's hair style preference by gender according to occassion. Data were collected through a survey of 149 males and 175 females and analyzed by SPSS packages. The results of this study were as follows : 1) Male prefers to short, straight and black hair while female prefers to shot, nature wave and black hair. 2) Both male and female don't prefer to permanent and hair dyeing. 3) On the occasion of job interview, both male and female prefer to short, straight and black hair. On the occasion of blind date, male prefers to short, straight and black hair while female prefers to short, natural wave and natural brown hair. On the occasion of matchmaker meeting for marriage, male prefers to short, straight and black hair while female prefers to short, natural wave and dark brown hair. On the occasion of club party, male prefers to middle length, straight and black hair while female prefers middle length, natural wave and natural brown hair. On the occasion of leasure time, male prefers to short, straight and black hair while female prefers to short, natural wave and natural brown hair. And both male and female prefer to use hats for skin protection during outdoor leasure time.