• Journal of Ocean Engineering and Technology
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• v.21 no.3 s.76
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• pp.65-70
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• 2007

There are many kinds of protection methods for marine structures, with varyingeconomical and environmental advantages. The coating protection method is being widely used in both continental and marine structures. In this study, by adding some additives, such as Zn powder(Zn), carbon black(CB) to epoxy anti-corrosive paint, the effect on the corrosion resistance was investigated throughan electrochemical method. The additive of Zn(20)+CB(10) showed the lowest passivity current density. Polarization resistance in both cyclic voltammogram and impedance measurement of an additive of Zn(20)+CB(10) was also the largest value, compared to other additives. Furthermore, rusting and bubbling was not observed on the surface of the test specimen with the additive of Zn(20)+CB(10), compared to other specimens. It is suggested that the corrosion resistance of the anti-corrosive paint can be improved by using some additives.

• English & American cultural studies
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• v.17 no.2
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• pp.89-109
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• 2017

This study focuses upon the fact that Wordsworth has a great interest in the epistemological understanding of nature. It denies that his early poems, such as An Evening Walk and Descriptive Sketches, only represent the subtleties of nature, according to the picturesque mode of the eighteenth century, without any other consideration about human mind. It tries to trace his effort to deal with the relationship between nature and mind, which is committed to the apprehension of Wordsworth's experience which shapes much of his later work. Prior to Wordsworth, or in his earlier days, both the picturesque description and the descriptive poetry tend to be two-dimensional. Staying away from the cold rules of painting and overcoming passivity, he prefers to contemplate nature through his emotions and tries to come close to the sublime sense. Therefore, his poetic strategy is to show that his poetic description of nature goes beyond the limits which these picturesque rules and colors impose. His readers get the feeling of how desperate he become trying to choose the suitable poetic language to express the relationship between nature and mind. He also has an interest in developing a character, Dorothy, to match what he thinks and to mediate what he intends to describe through his epistemological understanding of nature.

• English & American cultural studies
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• v.9 no.1
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• pp.297-321
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• 2009

The purpose of this study is to re-read the film of Dead Poets Society, specially focused on a feminist view. The film hides the strategy of recovering the traditional Patriarchal Society. At the beginning, the film resists the values of traditional society through John Keating. His unorthodox methods of teaching literature smack against the traditions of Welton Academy. Furthermore, he stresses on "Carpe Diem"—Seize the Day, the romantic values of free thinking, creativity, and individuality. The forces opposing Keating's philosophy are personified by Welton's rigid, old headmaster, Mr. Nolan, and the cruel, stubborn parent, Mr. Perry. Keating's romantic values are failed by their powerful, dominating attitudes. Effected by Keating's philosophy, Neil decides to pursue acting rather than medicine. He conflicts with his strict father. Finally frustrated by his authority, Neil commits suicide. And Keating is accused of inciting the boys to restart the Dead Poets Society, and at last he is fired. Keating and Neil are victimized by the Patriarchal society. Even though the film concentrates male characters at the all boys' school, it reveals the male angle of binary oppositions between men and women, subject and object, activity and passivity, presence and absence. In the film's dramatic conclusion, English class is now being temporarily taught by Nolan, who has the boys read from the very Pritchard essay they had ripped out at the start of the film. It symbolizes the triumph of the traditional logocentric society. However, influenced by Keating's unconventional attitudes, ultimately Welton Academy will be changed as it is embodied in its closing scene.

• The Journal of the Acoustical Society of Korea
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• v.20 no.3E
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• pp.18-24
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• 2001

Speaking rate represents how many phonemes in speech signal have in limited time. It is various and changeable depending on the speakers and the characters of each phoneme. The preprocessing to remove the effect of variety of speaking rate is necessary before recognizing the speech in the present speech recognition systems. So if it is possible to estimate the speaking rate in advance, the performance of speech recognition can be higher. However, the conventional speech vocoder decides the transmission rate for analyzing the fixed period no regardless of the variety rate of phoneme but if the speaking rate can be estimated in advance, it is very important information of speech to use in speech coding part as well. It increases the quality of sound in vocoder as well as applies the variable transmission rate. In this paper, we propose the method for presenting the speaking rate as parameter in speech vocoder. To estimate the speaking rate, the variety of phoneme is estimated and the Line Spectrum Pairs is used to estimate it. As a result of comparing the speaking rate performance with the proposed algorithm and passivity method worked by eye, error between two methods is 5.38% about fast utterance and 1.78% about slow utterance and the accuracy between two methods is 98% about slow utterance and 94% about fast utterances in 30 dB SNR and 10 dB SNR respectively.

• Corrosion Science and Technology
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• v.2 no.1
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• pp.7-11
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• 2003

Photoelectrochemical response and electrochemical impedance behavior was investigated for passive film formed on sputter-deposited Cr alloy in $0.1kmol{\cdot}m^{-3}$. Photoelectrochemical action spectrum could be separated into two components, which were considered to be derived from $Cr_2O_3$ ($E_g\sim3.6eV$) and $ Cr(OH)_3 $ ($E_g\sim2.5eV$). The band gap energy, $E_g$, of each component was almost constant for various applied potentials. polarization periods and alloying additives. The photoelectrochemical response showed negative photo current for most potentials in the passive region. Therefore, the photo current apparently exhibited p-typesemiconductor behavior. On the other hand, Mort-Schottky plot of the capacitance showed positive slope, which means that passive film formed on Cr alloy has n-type semiconductor property. These apparently conflicting results are rationally explained assuming that the passive film on Cr alloy formed in the acid solution has n-type semiconductor property with a fairly deep donor level in the band gap and forms an accumulation layer in the most of potential region in the passive state.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.632-638
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• 2011

In this paper, a nonlinear controller is proposed to track the desired velocity and to cancel sinusoidal disturbances. The proposed method consists of a velocity tracking controller and internal model principles (IMPs). For the design of the velocity tracking controller, mechanical and electrical dynamic controllers are independently designed. For the mechanical dynamics, the velocity tracking controller generates the desired quadrature current to track the desired velocity. The current tracking controller is designed to guarantee the desired quadrature current and to regulate the direct current. Therefore, the proposed velocity tracking controller has a field-oriented control. Since the controllers of the mechanical and electrical dynamics are independently designed, the stability of the closed-loop system is demonstrated using passivity. Since both the cogging torque and DC current errors act as sinusoidal disturbances in PMSM, we use four add-on type IMPs that preserve the merits and performance of the pre-designed controller without sacrificing the closed-loop stability. The performance of the proposed method is validated via simulations.

• Korean Journal of Metals and Materials
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• v.50 no.9
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• pp.619-627
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• 2012

One of the barriers limiting wide applications of magnesium alloys to various industries is their poor corrosion resistance. The corrosion properties of AZ91 magnesium alloy, which is the most popular magnesium casting alloy, are affected by microstructural and environmental factors. The corrosion properties of AZ91 magnesium alloy are affected by the corrosion properties of ${\alpha}-Mg$ and ${\beta}$ phases, the volume fraction and distribution of ${\beta}$ phase and area ratio of ${\alpha}-Mg/{\beta}$ phases. The corrosion properties of AZ91 magnesium alloy under various environments also change according to the passivity of films and types of corrosion products formed on its surface. The corrosion resistance of the magnesium alloys can be improved by microstructural control through the addition of alloying elements and optimization of the production process.

• Corrosion Science and Technology
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• v.20 no.6
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• pp.361-366
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• 2021

Localized corrosion behavior of Ni-based Inconel 718 alloy was investigated by electrochemical anodic polarization techniques in NACE TM 0177 A solution of 5 wt% NaCl + 0.5 wt% acetic acid at room temperature. After the solution heat treated at 1080 ℃ for 2.5 h, Inconel 718 was age-hardened at 780 ℃ for 8 h. The microstructure of the alloy surface was investigated by optical microscopic or scanning electron microscopic technique. The austenitic phase with the presence of metal carbides was observed on the surface of Inconel 718. Metal-carbides such as Nb-Mo and Ti-carbide with diameters of approximately 10 and 3 ㎛, respectively, were formed in Inconel 718. Anodic polarization results revealed that localized corrosion was observed at the interface between austenitic phase of a substrate and metal carbides. Difference in electrochemical property between a metal carbide and an austenitic substrate could provide an initiation site for localized corrosion of Inconel 718 surface.

• Corrosion Science and Technology
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• v.17 no.5
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• pp.203-210
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• 2018

This paper compares the inhibition properties of aspartic and lactic acid salts with nitrite ions and their effect on critical chloride concentration. The tests were carried employing carbon steel specimens in saturated lime solution with varying pH in the range between13 to 13.6. The critical chloride concentration was estimated through multiple specimen potentiostatic tests at potentials in the usual range for passive rebar in the alkaline concrete of atmospheric structures. During tests, chloride salt was added every 48 h until all the specimens showed localized attacks. The cumulative distribution curves, i.e. the number of corroded specimens as a function of the chlorides concentration was obtained. Furthermore, IR spectra were recorded for the evaluation of the presence of the organic inhibitors on the passivity film. The results confirmed the inhibitory effect of 0.1M aspartate comparable with nitrite ions, at a similar concentration. Addition of calcium lactate did not result in an increase in the critical chloride concentration. However, the formation of a massive scale containing the substance that could reduce the corrosion propagation was observed.

• Journal of the Korean Home Economics Association
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• v.49 no.1
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• pp.55-65
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• 2011

This study explored how a 5th grade girl from a divorced family recovered her femininity through the sandplay therapy. The client was referred by a social worker in her school because of maladjustments such as passivity in school work, poor peer relations, especially with girls, the usage of bad language and a lack of concern about her appearance. There were 41 sessions of the therapy. The first part of the therapy included 1-7 sessions, the middle part 8-35, and the final part 36-41. The client expressed her situation by showing guardians and a peeing boy and by seeking love in the first part. During the middle part she put copper ballerinas and needed to make them alive. In the final part she set figures facing each other who seemed to have mutual understandings and placed cars running well. The client recovered her femininity through the sandplay therapy in a free and protected space.