• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.12 s.103
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• pp.1239-1245
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• 2005

In this paper, a new predistortion linearizer using second harmonic components feedforwarding is proposed. The harmonic generator of the proposed predistorter that consists of a small signal amplifier extracts second harmonic signals. A vector modulator that modulate fundamental signal with second harmonic signals, generates the inverse third order intermodulation distortion signals and controls amplitude/phase of them with modulation factors. As a result, this linearizer is suppressed IMD3 signals of power amplifier effectively. The test results show that the third order IMD of power amplifier is suppressed more than 20 dB for CW two-tone signals. Also, it's improved the adjacent channel power ratio(ACPR) more than 5 dB for CDMA(IS-95) 4FA signals.

• Journal of the Korean School Mathematics Society
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• v.5 no.2
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• pp.71-82
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• 2002

This study purported to develop the learning materials for the optional activities of mathematics, apply them to the students, and examine the effect on the learner's interest and attitude to mathematics. In order to conduct this study, the learning materials for the mathematics optional activities were developed according to the units of grade 8-Ga and the developed learning materials of the mathematics optional activities were inputted in two classes for 18 units after the second grade middle school students in Daejeon area received the questionnaire regarding the learning attitude and the interest in the mathematics. After that, the questionnaire regarding the learning attitude and the interest in the mathematics and the examination regarding the response to the application of the learning materials for mathematics optional activities were conducted and did t-test. The results of the study as follows : First The learning materials applied exciting games for mathematics optional activities aroused interest in mathematics and made the learners have confidence in mathematics learning. Second, There was affirmative change in the interest and attitude to the mathematics learning with the application of the mathematics optional learning materials. Third The leaning materials of the mathematics optional activities made the learners think mathematical questions connected with the real life and try various ways to solve the questions. Here are some suggestions to study the development of the learning materials such as story, game, quiz and craft. First it is necessary to develop the learning materials applied the games or the real life matters connected with mathematics for all grade middle school students and use them in the mathematics optional activities. Second, many students feel a great interest in animation. moving picture, sound graphic, etc. If the multimedia learning materials included the real life matters or the games are developed, the learners will feel more interest in mathematics. Third, the systematic and economical support is continuously needed in order that teachers are given much time to study and the opportunity to attend the training course for the understanding of the optional activities and the development of the various learning materials.

• Journal of Korean Society of Rural Planning
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• v.24 no.3
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• pp.1-12
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• 2018

This study aims to offer base line data for efficient conflicts control measures by first, analyzing the current situation of the regional comprehensive development project and second, identifying level, type and cause of the conflicts appeared during the development business promotion. For this purpose, theoretical side of this study establishes a basic frame by reviewing the existing researches in order to analyze the characteristics of the conflicts between the participation subjects in the development business, and the empirical side conducts survey and analysis on the awareness on these conflicts. As a result of the analysis, the survey revealed the followings. First, the respondents were aware of the overall promotions of the business quite positively, second, the conflicts were considered as a major obstacle against the development project promotion just as the other negative factors, third, majority of the responses on the seriousness of the conflicts were neutral which meant that the conflicts could be deepened by situations, fourth, most respondents had positive recognition on the needs of conflict control training and its effectiveness, and last but not least, most respondents of the survey revealed their intentions to take parts in trouble shooting from the conflicts. Based on the results above, we were able to extract several elements to consider preparing the countermeasures for the conflicts. First, specific plan should be arranged and institutionalized in order to control the conflicts between the residents at the initial stage of the development business or even before. Second, the specific plan must lower its threshold for easy participation of the residents in that region and make the residents main body of the conflict control. Third, enhanced conflict control education must be provided to the residents of the region where comprehensive development plan is in progress or being prepared.

• Journal of Engineering Education Research
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• v.19 no.2
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• pp.102-111
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• 2016

This study was implemented for the purpose of analyzing the Job Competency level of accredited and non-accredited program's graduates. And we were seeking way to manage realistic and effective way of Accreditation of Engineering education. In order to achieve the purpose of this study, survey and FGI were done. The study was: accredited program's graduates thought more positively than non-accredited program's graduates, and graduates felt that 11 Job Competencies Level of Work Performance were lower than the needs of job performance. The conclusions of this study were summarized as follows: First, between accredited and non-accredited program's graduates, we could see significant recognition difference about the perception of the needs of job performance. This was because Design curriculum were reinforced and accredited program's graduates had attended design program at accredited program. Second, accredited program's graduates felt higher than non-accredited program's graduates about the perception of level of work performance. This was because the efforts for curriculum reorganizing and teaching methods improvement were done. Third, we could not find significant recognition difference about the perception of the needs for job performance and work level. That was because accredited and non-accredited program were not dealed seperately. The conclusions of this study are summarized as follows: First, The efforts for analyzing job competence of industry and reflecting the program curriculum are needed on the accredited program for engineering education. Second, Government should make the incentive policy about the companies which give some merits to the accreditation graduates, and monitor constantly their real working. Third, in order that the accreditation results can be trustful on staff recruiting or school choosing, accreditation should make outcome-based-evaluation which guarantees competence of graduates.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.11
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• pp.1582-1592
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• 2002

The purpose of this study is to suggest production planning model for women's apparel manufacturer, which are relevant to the situation of Korean clothing industry. The research was based on simulation method. The basic model for the simulation was developed based on the empirical data from six production fm. After verifying the basic model, low alternative production plans went through trial run. In order to suggest the application of these alternative production plans for various style numbers and lot sizes, the simulation results were compared in terms of product efficiency and product cost. The four alternative plans were as follows: 1. The first alternative was to spread out work loads among workers in order to resolve bottlenecks in work flow. So this was suited to manufacturers that had constant production without regard to changing seasons. 2. The second alternative was to merge the skirt and trouser production, which require less work load, in one line. In this line, a few machine was justified by production improvement. It was suited to cases which producted various style suits. The third and fourth alternative were using another subcontractor for assembling inner shell garments. These was compatible in manufacturers which had to product more styles and sizes of trousers and skirts than those of upper garments. 3. The third alternative was to reassign the same workers in production line. Thus, production was increased. 4. The fourth alternative was to except two worker in production line, so expenses of worker's wage was decreased. The four alternatives could be one of the cost effective manufacturing plans according to manufacturer situations.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.51-56
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• 2014

The solvolysis rate constants of 2,4-dimethoxybenzenesulfonyl chloride (1) in 30 different solvents are well correlated with the extended Grunwald-Winstein equation, using the $N_T$ solvent nucleophilicity scale and $Y_{Cl}$ solvent ionizing scale, with sensitivity values of $0.93{\pm}0.14$ and $0.65{\pm}0.06$ for l and m, respectively. These l and m values can be considered to support a $S_N2$ reaction pathway. The activation enthalpies (${\Delta}H^{\neq}$) were 12.4 to $14.6kcal{\cdot}mol^{-1}$ and the activation entropies (${\Delta}S^{\neq}$) were -15.5 to -$32.3kcal{\cdot}mol^{-1}{\cdot}K^{-1}$, which is consistent with the proposed bimolecular reaction mechanism. The solvent kinetic isotope effects (SKIE) were 1.74 to 1.86, which is also in accord with the $S_N2$ mechanism and was possibly assisted using a general-base catalysis. The values of product selectivity (S) for solvolyses of 1 in alcohol/water mixtures was 0.57 to 6.5, which is also consistent with the proposed bimolecular reaction mechanism. Third-order rate constants, $k_{ww}$ and $k_{aa}$, were calculated from the rate constants ($k_{obs}$), together with $k_{aw}$ and $k_{wa}$ calculated from the intercept and slope of the plot of 1/S vs. [water]/[alcohol]. The calculated rate constants, $k_{calc}$ ($k_{ww}$, $k_{aw}$, $k_{wa}$ and $k_{aa}$), are in satisfactory agreement with the experimental values, supporting the stoichiometric solvation effect analysis.

• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1089-1096
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• 2002

Solvolyses rate constants of trimethylacetyl chloride (2), isobutyryl chloride (3), diphenylacetyl chloride (4) and p-methoxyphenylacetyl chloride (5) in 2,2,2-trifluoroethanol (TFE)-water, 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP)-water and TFE-et hanol solvent systems at $10^{\circ}C$ are determined by a conductimetric method. Kinetic solvent isotope effects (KSIE) are reported from additional kinetic data for methanolyses of various substituted acetylchlorides in methanol According to the results of those reactions analyzed in terms of rate-rate profiles,extended Grunwald-Winstein type correlations, application of a third order reaction model based a general base catalyzed (GBC) and KSIE values. Regardless of the kind of neighboring groups (CH3- or Ph-groups) of reaction center, for aqueous fluorinated alcohol systems, solvolyses of 2, 3, 4, and 5 were exposed to the reaction with the same mechanism (a loose SN2 type mechanism by electrophilic solvation) controlled by a similarity of solvation of the transition sate (TS). Whereas, for TFE-ethanol solvent systems, the reactivity depended on whether substituted acetyl chloride have aromatic rings (Ph-) or alkyl groups (CH3-); the solvations by the predominant stoichiometric effect (third order reaction mechanism by GBC and/or by push-pull type) for Ph- groups (4 and 5) and the same solvation effects as those shown in TFE-water solvent systems for CH3- groups (2 and 3) were exhibited Such phenomena can be interpreted as having relevance to the inductive effect ( $\sigmaI)$ of substituted groups; the plot of log (KSIE) vs. ${\sigma}I$ parameter give an acceptable the linear correlation with r = 0.970 (slope = 0.44 $\pm$ 0.06, n = 5).

• Journal of Digital Convergence
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• v.9 no.4
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• pp.169-179
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• 2011

The purpose of this study are as follows. First, to analyze digital convergence level of convergence generation to demographic variables. Second, the convergence level to digital device and using frequency to digital service. Third, the convergence level to digital service and using frequency to digital service. The research methods FGI, the interview with IT expert group and survey. The results of research are as follows. First, 30 aging, expert group, higher education group over graduate school are actively using and participated. Second, high level of convergence device are smart-phone, tablet PC, net-book are in order. high level of convergence service are SNS service, twitter, uee, portal messenger and app store, e-Book, web hard are in order. Third, The convergence generation enjoying app-store of smartphone, wireless game and more participating facebook/cyworld twitter, Portal, internet community.

• Korean Institute of Interior Design Journal
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• v.16 no.6
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• pp.136-143
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• 2007

In case of commercial area of underground commercial area that occupy large amount of space among underground space, the lighting plays a very important role in terms of user's psychological and physiological side. The purpose of this research is to suggest the direction of lighting design of underground commercial area for revitalization of urban function. Spacial scope of this research were adjusted as 8 underground commercial area in Seoul. Scope of content of this research is about lighting plan of underground commercial area. Research methods are as follows: First, we identified the psychological and physiological problem of the underground space which appears in preceding research and the literature. In order to make the design element which is necessary to an underground space it executed this research method. By this research method we made the design element which is necessary to an underground space. Second, Through site visits, illumination level and lighting plans were studied by each category. Third, we presented the direction of illumination plan of each space in underground commercial area We could conclude a conclusion as following through this research. First, lighting plan of underground commercial area should solve user's psychological, physiological problems and should take advantage of the traits of each space. Second, the usage of space of underground commercial area changes as time pass, a lighting plan is needed in order to cope with this. Third, a lighting plan is needed for user's rest within underground commercial area. Fourth, detailed lighting plan is needed for space users of underground commercial area.

• Journal of the Korean Society of Clothing and Textiles
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• v.33 no.9
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• pp.1374-1385
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• 2009

This study focuses on three points. First, how designers develop clothing and cosmetic culture (which reflect time and culture) into other fashion products in order to verify that attire and makeup can be the objects of aesthetics in addition to functionality. Second, why the fashion design of Christian Dior has been continuously popular for women of all ages and countries in the development of fashion, attire, and makeup. Third, this study analyzes how the aesthetical characteristics of the fashion of Christian Dior are reflected in clothing and cosmetic culture in order to clarify the brand outlook on attire and makeup as a source of France's luxury fashion industry. The philosophical characteristics of Dior's fashion were studied based on existing literature. First, her childhood background (that became the motif of Dior's design) and the philosophical ideology of fashion design, perfume, and beauty were the focus of this study. Second, this study examined how consciousness on beauty expressed in hairstyle, perfume, and cosmetics is expressed in connection with clothing. Third, the background with which Dior's fashion and perfume business became successful is examined in addition the necessity of the image strategy for success in the cosmetics market was studied. Domestic and international books on clothing and cosmetics, preceding studies, the internet, and related magazines are utilized to consider the cosmetics and beauty fashion of Dior. The results of this study show how Korean fashion and cosmetic culture can further globalize. This study encompasses the period of 1905 when Christian Dior was born until 1957 when he died of a heart attack; it also deals with well-known designers of the Christian Dior House from Yves Saint Laurent of 1957 to John Galliano of the present.