• Title/Summary/Keyword: Clean class

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Dehydration Reaction of Fructose to 5-Hydroxymethylfurfural over Various Keggin-type Heteropolyacids (Keggin형 헤테로폴리산에 의한 과당의 5-하이드록시메틸퍼퓨랄로의 전환을 위한 탈수반응)

  • Baek, Ja-Yeon;Yun, Hyeong-Jin;Kim, Nam-Dong;Choi, Young-Bo;Yi, Jong-Heop
    • Clean Technology
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    • v.16 no.3
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    • pp.220-228
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    • 2010
  • Four Keggin-type heteropolyacids, $H_nXM_{12}O_{40}$(X = P and Si, M = W and Mo) that were substituted with heteroatom and polyatom were applied to the dehydration reaction of fructose to 5-hydroxymethylfurfural (HMF). The results showed that the acid became stronger when the heteroatom and polyatom were substituted with P and W than the cases of Si and Mo, respectively. However, the amount of acidic sites increased with the decrease in the acid strength, resulting in the change of the catalytic activity of heteropolyacids in the dehydration reaction. The experimental results revealed that four different heteropolyacids produced similar amounts of HMF via the dehydration reaction of fructose due to the counterbalancing effect between the amount of active sites, which is related to the catalytic activity of heteropolyacids, and the softness of polyanion. In addition, it was observed that the prepared heteropolyacids showed good structural stability after heat treatment at $200^{\circ}C$.

The Effect of Environment Worksheet on the Elementary Students' Environmental Perceptions & Behavior (워크시트를 활용한 환경수업이 초등학생들의 환경인식 및 환경행동에 미치는 효과)

  • Kim, Soon-Shik
    • Journal of Environmental Science International
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    • v.20 no.5
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    • pp.611-621
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    • 2011
  • This study aims to find out an effect of 3 types of environment worksheets used for 5th elementary graders's environmental class on their environmental perceptions and behavior. 104 of 5th graders in M elementary school in Ulsan Metropolitan City were selected and divided into A group(35), B group(34) and C group(35) for this study, and to A group, a class used worksheet of the photo taken clean, unpolluted environment, and to B group, a class used worksheet of the photo taken polluted environment and to C group, a class used worksheet of only text without photo were carried out. The worksheet used class was conducted 5 times, and then after the classes, the student's change in environmental perceptions and behavior by group was put into verification Below are the study results. First, the worksheets used for the environment class have incurred significant differences in student's environmental perceptions by their types. A. B groups were higher than C group in their post-test environmental perceptions score, a statistically significant differences. Meanwhile, statistically insignificant differences appeared in environmental perceptions score between A and B groups. Second, the type of worksheet used for environment class represented considerable differences in he students' environmental behavior. A group was higher than B. C groups in post test environment behavior score, the difference of which was statistically significant. While statistically insignificant difference represented in environmental behavior between B, C groups. Third, the both types of worksheets of the photo of positive environment and that of negative environment appeared to be effective statistically in changing the elementary students' environmental behavior, while the worksheets of the photo of positive environment appeared to be effective statistically in their environmental behavior.

열진공시험시의 위성체 오염측정 및 분석

  • 조혁진;문귀원;이상훈;서희준;최석원
    • Bulletin of the Korean Space Science Society
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    • 2004.04a
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    • pp.75-75
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    • 2004
  • 위성체에 대한 오염의 측정과 관리는 매우 정밀한 광학계나 기타 오염 민감 표면에 큰 영향을 미치기 때문에 위성이 발사되기 전까지 주의 깊게 수행되어야 한다. 대부분의 기간동안 위성은 청정실(clean class 10,000)에서 보관 및 운용되기 때문에 측정 및 분석이 쉽게 이루어질 수 있으나 위성의 궤도환경모사를 위한 열진공시험시의 오염 측정 및 분석은 상압, 상온의 청정실 내부에서의 그것과는 차이가 있다. (중략)

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Robust Video-Based Barcode Recognition via Online Sequential Filtering

  • Kim, Minyoung
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.14 no.1
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    • pp.8-16
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    • 2014
  • We consider the visual barcode recognition problem in a noisy video data setup. Unlike most existing single-frame recognizers that require considerable user effort to acquire clean, motionless and blur-free barcode signals, we eliminate such extra human efforts by proposing a robust video-based barcode recognition algorithm. We deal with a sequence of noisy blurred barcode image frames by posing it as an online filtering problem. In the proposed dynamic recognition model, at each frame we infer the blur level of the frame as well as the digit class label. In contrast to a frame-by-frame based approach with heuristic majority voting scheme, the class labels and frame-wise noise levels are propagated along the frame sequences in our model, and hence we exploit all cues from noisy frames that are potentially useful for predicting the barcode label in a probabilistically reasonable sense. We also suggest a visual barcode tracking approach that efficiently localizes barcode areas in video frames. The effectiveness of the proposed approaches is demonstrated empirically on both synthetic and real data setup.

Public Space, Urban Culture and Modernity: Cafes in Modern Shanghai (1900-1949)

  • Jiang, Wenjun
    • Journal of East-Asian Urban History
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    • v.2 no.1
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    • pp.27-63
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    • 2020
  • The emergence of coffee shops and other public spaces in modern Shanghai shows the appearance of the "mass" centered on the middle class. Furthermore, we can further explore the different development paths of the publicity of modern Chinese urban society. The emergence of new public leisure spaces, such as cafes, provides a model of modern life style and a stage of daily publicity for the middle class in Shanghai. With the convenience provided by this kind of public space, people are able to clean up their old opinions and be better at accepting new ideas. A more sensitive and flexible public opinion of Enlightenment has gradually formed in urban life.

Developement of Class 1 Clean Room Devices (CLASS 1 초청정장치 개발)

  • Seo, Suck-Chung
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.18 no.2
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    • pp.130-137
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    • 1989
  • 본 논문은 1. 초청정기술의 현황, 2. 초청정장치의 요소기술, 3. 초청정장치의 개요, 4. 국부청정실의 기본계획에 대해 기술하고 있다. 1. 초청정기술의 현황에서는, 본 연구수행의 방향설정을 위해 미국과 일본의 관련 학${\cdot}$협회의 동향 및 최근에 발표된 논문에 근거한 초청정기술의 연구경향과 과제 등을 파악 분석했다. 2. 초청정장치의 요소기술에서는, 초청정장치 개발에 필요한 미립자제거, 환경조건과 오염제어 기술을 확립하기 위해, Filter와 System Ceiling 방식, 온${\cdot}$습도, 진동, 정전기제어 기술에 관한 문제점과 대책에 대해 검토했다. 3. 초청정장치의 개요에서는, 초청정장치로써 대표적인 클린벤취의 관련규격, 설계요점 등을 검토하여 설계를 위한 기초자료로 삼았다. 4. 국부청정실의 기본계획에서는 상기의 요소기술과 기초자료에 근거하여 본 연구를 수행하기 위한 Line 형의 클린터널 유닛의 기본계획을 수립했다.

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Needs of Housing in Home Economics Curriculum of Home Economics Teachers (가정교과 주생활단원에 대한 가정과 교사의 평가 및 내용필요도)

  • Goh, Bok-Soon;Park, Kyoung-Ok
    • Korean Journal of Human Ecology
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    • v.10 no.3
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    • pp.303-315
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    • 2001
  • The purpose of this study is to evaluate the housing unit and investigate needs of housing in Home Economics curriculum of Home Economics teachers. The questionnaire survey was conducted 98 teachers participated in the minor training course in Chungbuk, August of 2000. When the teachers made their class in the section of housing, they emphasized respectively as the textual order: the space of housing and family life, the utilization of space, clean of residing circumstance in the middle school: and in the high school there was also concerned to the textual order: choice of housing, the house planning, interior design, maintenance of house. The teachers focused into the arrange of furniture and interior design for the students in the class, drawing of a plan in the contents of practical experience and performance. According to the survey results, the main point of class in housing should be emphasized the arranging of own room and function of other spaces in house for the students in the middle school. The high school curriculum should focus on the practical area to connect with the interior design. And in the section of housing it was needed to add the contents of management in the multi-family housing, housing problems, neighborhood environment for elderly, and also community planning.

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Wig usage investigation which symbolizes the socio-economic status (Egypt$\sim$17C)

  • Jung, Hyun-Jin;Kim, Sung-Nam
    • Journal of Fashion Business
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    • v.9 no.6
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    • pp.56-70
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    • 2005
  • This study investigates historically difference by age of wig banishments that symbolize social-economic status from West Egypt era baroque age as qualitative study that use secondary bibliographic data, there is purpose. Conclusion of this study is as following. Because wig putting on that symbolize among several usages of wig putting on, socio-economic status until 17th century baroque age from ancient Egypt is been in fashion through privilege class lower classes as well as upper class wig putting on attain. Ancient wig putting on became measure that divide class because differ material of wig or one dimension, shape (style) and length became linear measure that it can aim wealth's emblem that putting on of long wave wig and whole wig that differ lust has many wig though was in fashion though whole wig and were in fashion arriving to Renaissance. That it becomes France clean fingernails' necessaries as Louis the 14th that ready crux of absolute authority establishment of France Court put wig from depilation to count 17 was clear socio-economic status etc. symbol measure inclination. Go without question status or position, wealth and churchman puts wig so that can know special sex of weapon of where the soldiers are belonged as well as put wig and wig putting on was parted according to job and lower classes participated in fashion of wig putting on. Wig putting on that become measure that symbolize job or status in this baroque age, position, wealth etc. gave absolute influence in wig fashion in 18th century.

The Effect of Engineering Design Based Ocean Clean Up Lesson on STEAM Attitude and Creative Engineering Problem Solving Propensity (공학설계기반 오션클린업(Ocean Clean-up) 수업이 STEAM태도와 창의공학적 문제해결성향에 미치는 효과)

  • DongYoung Lee;Hyojin Yi;Younkyeong Nam
    • Journal of the Korean earth science society
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    • v.44 no.1
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    • pp.79-89
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    • 2023
  • The purpose of this study was to investigate the effects of engineering design-based ocean cleanup classes on STEAM attitudes and creative engineering problem-solving dispositions. Furthermore, during this process, we tried to determine interesting points that students encountered in engineering design-based classes. For this study, a science class with six lessons based on engineering design was developed and reviewed by a professor who majored in engineering design, along with five engineering design experts with a master's degree or higher. The subject of the class was selected as the design and implementation of scientific and engineering measures to reduce marine pollution based on the method implemented in an actual Ocean Clean-up Project. The engineering design process utilized the engineering design model presented by NGSS (2013), and was configured to experience redesign through the optimization process. To verify effectiveness, the STEAM attitude questionnaire developed by Park et al. (2019) and the creative engineering problemsolving propensity test tool developed by Kang and Nam (2016) were used. A pre and post t-test was used for statistical analysis for the effectiveness test. In addition, the contents of interesting points experienced by the learners were transcribed after receiving descriptive responses, and were analyzed and visualized through degree centrality analysis. Results confirmed that engineering design in science classes had a positive effect on both STEAM attitude and creative engineering problem-solving disposition (p< .05). In addition, as a result of unstructured data analysis, science and engineering knowledge, engineering experience, and cooperation and collaboration appeared as factors in which learners were interested in learning, confirming that engineering experience was the main factor.

Design Study of Fuel Supply System for 5MW-class Bio Gasturbine by Using Food Waste Water (5MW급 바이오 가스터빈용 전처리시스템 설계연구)

  • Hur, Kwang-Beom;Park, Jung-Keuk;Yun, Eun-Young;Lee, Jung-Bin
    • New & Renewable Energy
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    • v.7 no.2
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    • pp.10-17
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    • 2011
  • Korea is the 11th largest energy consumption country and 96% of its total energy consumption depends on imports from overseas. Therefore it is a very important task to secure renewable energy sources which can reduce both the carbon-dioxide emission and dependency on overseas energy imports. Among the various renewable energy sources, organic wastes are important sources. In Korea, 113 million toe of methane is generated from organic wastes annually, but only 3.7% is effectively used for energy conversion. Thus, it is very important to make better use of organic wastes, especially for power generation. The goals of this project are to develope the fuel supplying system of Bio Gasturbine (GT) for 5MW-class co-generation system. The fuel supplying system mainly consists of $H_2S$ removal system, Bio Gas compression system, Siloxane removal system and moisture separating systems. The fuel requirement of 5MW-class GT is at around 60% of $CH_4$, $H_2S$ (<30 ppm), Siloxane(<10 mg/$nm^3$) and supply pressure (> 25 bar) from biogas compressor. Main mechnical charateristics of Bio Gasturbine system have the specific performance; 1) high speed turbine speed (12,840 rpm) 2) very clean emmission NOx (<50 ppm) 3) high efficiency of energy conversion rate. This paper focuses on the development of design technology for food waste biogas pretreatment system for 5MW-class biogas turbine. The study also has the plan to replace the fuel of gas turbine and other distributed power systems. As the increase of bioenergy, this system help to contribute to spread more New & Renewable Energy and the establishment of Renewable Portfolio Standards (RPS) for Korea.