• Title/Summary/Keyword: IMPROVE

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Studies on the Activity Properties of Pd-only Three-Way Catalyst for the Purification of Automobile Exhaust Emissions (자동차 배기가스 정화용 Pb-only 삼원촉매의 활성특성에 관한 연구)

  • 신병선;김상수;이길우;정명근;배재호;정석진
    • Journal of Korean Society for Atmospheric Environment
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    • v.15 no.5
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    • pp.667-676
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    • 1999
  • The roles of ceria on three-way catalyst is to improve the noble metal dispersion and thermal stability of support ${\gamma}$-$Al_2O_3$. And, ceria has a oxygen storage capacity(OSC) under fuel rich/lean conditions to improve the operating windows of NOx, THC and CO conversion. However, ceria has weak thermal stability under high temperature due to the crystallite growth. So that, the OSC of ceria is decreased, and then the conversions of NOx, THC and CO is decreased. One way of enhancing the thermal stability and NOx, THC and CO conversion Pd-only catalyst is to improve as well as its thermal stability and oxygen storage capacity of the ceria. Especially, the appropriate mixing ratios of bulk and stabilized ceria are very important for designing principles of Pd-only three-way catalysts. In this paper, we discussed the thermal properties of stabilizedand unstabilized (bulk) ceria, and the oxygen storage capacity (OSC) of catalysts, and found the correlation between activity and the OSC of Pd-only catalysts with various different mixing ratios of bulk and stabilized ceria. Finally, we propose the design principles to improve the thermal stability of washcoated Pd-only catalysts.

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How to improve English communicative proficiency in primary schools by performing games and songs in English classes (게임과 노래를 통한 초등영어 학습지도)

  • Im, Byung-Bin
    • English Language & Literature Teaching
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    • no.4
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    • pp.85-116
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    • 1998
  • Since the 1980's language teachers have been urged to take more communicatively oriented practice instead of traditional audio-lingual and grammar-translation instruction. However, there are many reasons why communication-centered teaching approaches haven't been easily adopted in Korea. First of all many English teachers haven't been prepared for communicative language teaching. And class size is very large. Another reason is that students' reading and writing skills are more important than their speaking and listening skills to enter colleges. But the world has been changing rapidly. We have many chances to meet foreigners and to talk to them. So many students want to improve their communicative proficiency. The purpose of this study is how to improve their communicative proficiency by performing games in English classes. There are many advantages of using games and songs in the classroom. First, games are motivating and challenging. Second, students can improve their four skills(speaking, writing, listening and reading skills) by using games and songs. Thirdly, games and songs help students to study English without their conscious efforts and to practice English repeatedly because they are interested in them. Fourthly, games and songs create a meaningful context for language use. Lastly, students can learn English with less tension and anxiety. Therefore, English games and songs are worthy of using in classes. To use English games and song more effectively, more various and useful materials have to be developed for English teachers and have to be introduced pertinently into classes.

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A Study on the Effective Surge Protection Method from Induced Lightning Surge to Improve Isolate Grounding to Common Grounding (낙뢰 Surge 방호를 위한, 독립접지를 공통접지로 개선하는 효율적인 방법에 대한 연구)

  • Woo, Jea-Wook
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2013.10a
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    • pp.215-218
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    • 2013
  • This paper proposes the effective method to improve the protection from induced lightning surge by making common grounding from individual grounding. Common grounding under equipotential principle is more effective than individual grounding for lightning surge protection, and so common grounding is indicated as international technical standard under the AC power supply system with neutral line. So, this paper is to propose the effective way of induced lightning surge protection method for currently installed power supply system which has no neutral grounded line and individual grounding which are weak for lightning surge protection. This proposal can improve the power supply system as has neutral line, and improve the grounding system to common grounding system. And also this paper proposes to make effective equipotential system with voltage variable shunting devices for lightning surge protection.

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Development of Permanent Magnet Synchronous Motor for High-speed Electric Multiple Unit - 400km/h eXperimen (차세대 고속전철용 영구자석동기 전동기 개발)

  • Kim, Jung-Chul;Kim, Bong-Chul;Park, Yeong-Ho;Kim, Chul-Ho
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.470-474
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    • 2010
  • Up until now, power centralized trains have been produced due to the maintenance convenience and comfortableness, but there are some problems, such as limitation of viscosity and maintenance difficulty of railroad due to recently increasing axle mass. In order to improve the problems, power decentralized trains have been developed to improve traction power. In the case of using electrical braking system, it is possible to improve braking friction power. Induction motors have been developed for power decentralized high speed train because of less structural defection, and low maintenance and production cost. However, induction motors have limitations, such as assuring enough power capacity and efficiency with reduced size. PMSM (Permanent magnet synchronous motor) have been newly developed to improve shortcomings of induction motors. The PMSM can be produced small and light weighted. Also if the PMSM and induction motors have the same size and power capacity, the PMSM have better power efficiency. In this pater, the prototype and modified type of PMSM for "High-speed Electric Multiple Unit-400km/h eXperimmen" will be introduced.

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A study on developing students′ positive attitude toward mathematics in commercial high schools (상업계 고등학생의 수학에 대한 태도 향상 방안 연구)

  • 최택영;박두길
    • Journal of the Korean School Mathematics Society
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    • v.5 no.2
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    • pp.111-128
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    • 2002
  • This study concentrates on investigating teaching methods with which students of a commercial high school, located in a rural district, can improve their attitude toward mathematics. To begin with, this study examines the causes which make the students take negative views against it through a survey of their current attitude toward mathematics; offers a special class for them to develop a positive attitude toward it: and then, figure out how much they change their academic attitude within the class and how much they improve their academic achievement as well. The results can be summarized as follows: First, the experimental groups showed terribly negative attitudes toward mathematics, and their academic achievements were very low compared with students of academic high schools nearby, Second, thanks to the special class given to improve their attitude toward mathematics, the experimental groups ended up taking a meaningful positive attitude toward it and developing their academic achievements in the subject. On the other hand, the controlled groups without any chance to receive special lessons remained unchanged. Therefore, it is indicated that a special lesson, properly provided, would play an important role to improve students' positive attitude toward mathematics and develop their basic academic achievements.

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The Improvement of the Korea Trade Finance Services (중소기업금융으로서 무역금융제도의 개선방안)

  • PARK, Kwang-So;HWANG, Ji-Hyeon;ZHOU, Ling-Ke
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.75
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    • pp.117-136
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    • 2017
  • Trade finance services have been played an important role in the Korea trade development history since 1960's. These days the trade environment is confronted by the 4th Industrial revolution and new trade protectionism. So we need to improve the Korea Trade Finance Services in order to improve Korea trade volume. Bank of Korea(BOK) also revised the Rule of Korea Trade Finance in 2014 and enlarged the trade fund for commercial banks where they handle the trade finance to small and medium enterprises(SME) in 2016. This article handle the current state and problems of Korea trade finance services and suggest the improvement measures as follows; First, the commercial banks, which handle trade finance fund, should improve the customs and practice of judge loan for SMEs. Second, the export volume counting rule for trade loan should harmonize between BOK's Rule and Foreign Trade Management Regulation under the Foreign Trade Act. Third, the processing trade and intermediate trade also can use the trade finance like other trade. Fourth, Trade finance should be in balance between export and import finance to defend the new protectionism. It means that the trade finance should expand to import in the certain conditions. Lastly, the related trade promotion agencies and their employees should improve their skills and abilities for handling trade finance.

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Oriental Medicine Music therapy for The treatment of Sasangin's disdases (사상체질인(四象體質人)의 병증(病證) 치료를 위한 한방음악치료(韓方音樂治療)에 관한 연구;장부대소(臟腑大小)와 호흡출납(呼吸出納)을 중심으로)

  • Lee, Seung-Hyun
    • Journal of Korean Medical classics
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    • v.20 no.4
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    • pp.119-126
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    • 2007
  • The biological and pathological states of lung, spleen, liver and kidneys are determined by nature and emotion of sorrow, anger, joy and pleasure, It is considered that the music, besides medicine or acupuncture, can be a way of treating as a therapeutics for the treatment of Sasangin's diseases. This study is to find out a way of music therapy for the treatment of Sasangin's diseases. The ways of music therapy in each constitution based on 'the great and small of Viscera and Bowels' and 'the exhale and inhale, the drawing in and sending out' are as follows: 1. In case of Soeumin, a skip going up melodic progression, dotted rhythm and the major triad harmonic progression are recommended to improve the Qi of warm Yang. 2. In case of Soyangin, in regular sequence down melodic progression, a sixteenth note and the minor triad harmonic progression are recommended to improve the Qi of cool Yin. 3. In case of Taeumin, in regular sequence going up melodic progression, a sixteenth note and the bright and active the major triad harmonic progression are recommended to improve the Qi of dispersing exhale. 4. In case of Taeyangin, a skip down melodic progression, a quarter note and a diminished triad harmonic progression are recommended to improve the Qi of gathering inhale.

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Low-light Image Enhancement Based on Frame Difference and Tone Mapping (프레임 차와 톤 매핑을 이용한 저조도 영상 향상)

  • Jeong, Yunju;Lee, Yeonghak;Shim, Jaechang;Jung, Soon Ki
    • Journal of Korea Multimedia Society
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    • v.21 no.9
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    • pp.1044-1051
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    • 2018
  • In this paper, we propose a new method to improve low light image. In order to improve the image quality of a night image with a moving object as much as the quality of a daytime image, the following tasks were performed. Firstly, we reduce the noisy of the input night image and improve the night image by the tone mapping method. Secondly, we segment the input night image into a foreground with motion and a background without motion. The motion is detected using both the difference between the current frame and the previous frame and the difference between the current frame and the night background image. The background region of the night image takes pixels from corresponding positions in the daytime image. The foreground regions of the night image take the pixels from the corresponding positions of the image which is improved by the tone mapping method. Experimental results show that the proposed method can improve the visual quality more clearly than the existing methods.

Effects of Beating of Cotton Linter Pulps with Titanium Dioxide on Paper Properties (면섬유 고해 시 TiO2 혼합처리가 종이물성에 미치는 영향)

  • Kil, Jung-Ha;Shin, Hyeon-Sik;Lee, Jin-Ho;Park, Jong-Moon
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.45 no.2
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    • pp.27-32
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    • 2013
  • To improve the physical properties, such as swelling and flexibility, of the cotton fiber, sodium hydroxide or cellulase was used for pretreatment before the beating process. Titanium dioxide was blended during beating process to improve the fibrillation of cotton fibers and even distribution of fillers to cotton fibers. Blending with titanium dioxide during beating process, led to improve the tensile strength and beating degree This treatment also improved the opacity, resulted by well dispersed titanium dioxide during blending. By the blending of titanium dioxide during beating process, similar impact of cotton fiber with cellulase or sodium hydroxide pretreatment was achieved. To improve the tensile strength and opacity of cotton paper simultaneously, titanium dioxide blending in during beating process was found as effective treatment.

An Optimization Technique to Improve Readability of CSS (CSS 가독성 향상을 위한 최적화기법)

  • Jung, Woo-Sung;Lee, Eun-Joo
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.7
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    • pp.99-108
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    • 2010
  • For effective maintenance for web applications, it is necessary to improve the readability of the source pages. Though CSS(Cascading Style Sheet) belongs to pure presentation layer in various web constituent entities, CSS codes are often used by inlning and they are sometimes automatically generated by web development tools. The existing studies on CSS optimization have only focused on reducing the size of codes and they did not incorporate the readability or the reusability. In this paper, CSS codes are structured and several criteria for readability are defined to improve the readabilty and reusability. Based on them, the algorithm to improve the readability are proposed. Finally, case study are presented to show the applicability of the proposed algorithm.