• Title/Summary/Keyword: Self cleaning

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The Effects of Chicken-Rearing Activity on Character, Emotion and Self-esteem of Middle School Students (닭 돌보기 활동이 중학생의 인성, 정서 및 자아존중감에 미치는 효과)

  • Yoo, Ji Hyun;Jin, Hyun Ju
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.3
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    • pp.173-179
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    • 2020
  • The purpose of this study was to examine whether chicken-rearing activity is effective on the character, emotion and self-esteem of middle school students, as a pilot study for the development of an animal-assisted education program based on chicken-rearing activity. School was selected as the place where students have experience with raising animals before and no poultry farms were located near the school. The experimental group consisted of 11 students as the chicken-rearing group. The conducted activities were greeting chickens, cleaning henhouse, feeding them, and picking eggs up for five months. Character, emotion and self-esteem scales were used as test tools, and pre-testing and post-testing were conducted to verify the effectiveness of the study. Data collected were analyzed by using SPSS Win 25.0 statistical program. As a result, the character, emotional stability and self-esteem of middle school students who participated in chicken-rearing activity were improved. This study is meaningful in that the chicken-rearing activity proved to be effective for the character, emotion and self-esteem of middle school students and prepared an experimental case study for developing an animal-assisted education program based on chicken-rearing activity. It is expected to be useful as basic data of animal-assisted education for adolescents in school.

A study on the functional coatings using silicone resin of Architectural membrane structures products (건축용 막구조 제품의 실리콘 기능성 코팅에 관한 연구)

  • Choi, Yun-Sung;Lee, Jang-Hun;Yoon, Nam-Sik;Kim, Su-Hong;Yoo, Gu-Geun
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2012.03a
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    • pp.106-106
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    • 2012
  • 막구조(Membrane structure)란 건축분야에서 "fabric structure" 또는 tension structure"와 같이 사용되는 용어로 코팅된 직물(coated fabrics)을 주재료로 사용하는 구조를 말한다. 특히 구조체로서 연성의 막을 이용 이것에 초기 장력을 주어 강성을 늘림으로서 외부하중에 대하여 안정된 형태를 유지하는 장점을 갖고 있다. 초기 창안된 독일의 온화한 기후에 적용되는 반면 한국이나 일본에는 60m/sec를 넘나드는 태풍의 피해와 많은 적설량을 보이는 기후적 제약으로 발달되지 못하였다. 그러나 최근 새로운 소재의 막구조 제품 개발과 구조해석 방법 및 시공기술 등이 개발되어 보편화되어지고 있는 실정이다. 막구조용 재료로 사용되는 섬유소재는 주로 Polyester직물을 기재로 한 PVC 코팅 제품으로 일반 PVC 막재는 장력이 약하고, 광선에 의한 물성이 쉽게 변화되어 내구연한이 5~15년에 불과하다. 유리섬유나 아라미드섬유 등으로 제직한 기재에 고내열 실리콘이나 PTFE 수지를 코팅한 제품은 약품에 대한 내구성이 높고 자외선에 대해서는 매우 큰 저항성을 가지기 때문에 내구연한이 10년에서 30년 까지도 향상된다. 그러나 실리콘 코팅막은 세계적으로 가장 좋은 막재로 알려졌으나 자정능력(Self Cleaning)에 문제가 발생되어 사용량이 감소 추세라고 할 수 있다. 일반적인 코팅 가공의 경우 MEK, Toluene, DMF 등과 같은 유기용제를 다량 사용함에 따라 작업환경 및 대기오염, 화재 위험 등의 문제점이 있으며 특히 가공시 잔류되는 유기용제의 심각성이 대두되고 있는 상황이다. 이와 같이 코팅 가공제 자체를 친환경적인 물질로 대체하여 각종 환경규제에 대응하고 유해 폐기물의 발생을 줄일 수 있는 코팅 가공제 및 가공기술 개발이 절실하다. 이에 본 연구에서는 Glass-Fiber, Aramid 등의 슈퍼 섬유와 고 강력 섬유 등을 이용하여 PTFE 코팅제품과 비슷한 수준의 성능을 부여하는 무용제형 실리콘 코팅 수지를 개발하고 내구성능 향상, Self Cleaning성, 난연성, 자외선 차단, 인장강도 및 인열 강도의 향상 등 다양한 기능성을 부여하는 최적의 환경 친화적 코팅 공정 기술을 개발하여 차세대 건축용 막구조 제품을 개발하고자 한다.

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The Study of Development of Color-Mud for Boryeong Mud Festival by Color Pigment (착색안료를 이용한 보령머드축제용 유색머드의 개발)

  • Shim, Seung-Bo;Oh, Seong-Geun;Hong, Kyung-Hee;Chun, Yong-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.6
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    • pp.2300-2305
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    • 2010
  • This study was performed about color-contained mud to provide fun and diversity for the event of mud self massage as a core program of Boryeong Mud Festival which has become one of representative festivals in Korea. Adjusting its own lower brightness of mud and based on the primary study performed about the expressivity of yellowish colors, inorganic colors (oxidized steel in red, ultra marine pink, ultra marine blue, chrome oxide green) were added for the development of colored mud in diverse colors on the basis of Korean traditional colors. It had been judged about each expressivity of color by methods of colormeter, naked eyes inspection and feeling of usage, etc. For the color decided, it had been examined about the coloring when it got wet with the cleaning condition so that it can be used for the event of mud self massage as a program of Boryeong Mud Festival to increase diversity of the Festival and also attempted to develope colored mud to show Korean traditional colors.

The Study on In-situ Diagnosis of Chemical Vapor Deposition Processes (화학기상증착 진공공정의 실시간 진단연구)

  • Jeon, Ki-Moon;Shin, Jae-Soo;Lim, Sung-Kyu;Park, Sang-Hyun;Kang, Byoung-Koo;Yune, Jin-Uk;Yun, Ju-Young;Shin, Yong-Hyeon;Kang, Sang-Woo
    • Journal of the Korean Vacuum Society
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    • v.20 no.2
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    • pp.86-92
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    • 2011
  • The diagnosis studies of the process of chemical vapor deposition were carried out by using in-situ particle monitor (ISPM) and self-plasma optical emission spectroscopy (SPOES). We used the two kinds of equipments such as the silicon plasma enhanced chemical vapor deposition system with silane gas and the borophosphosilicate glass depositon system for monitoring. Using two sensors, we tried to verify the diagnostic and in-situ sensing ability of by-product gases and contaminant particles at the deposition and cleaning steps. The processes were controlled as a function of precess temperature, operating pressure, plasma power, etc. and two sensors were installed at the exhaust line and contiguous with each other. the correlation of data (by-product species and particles) measured by sensors were also investigated.

Work Conditions and Practices in Norwegian Fire Departments From 1950 Until Today: A Survey on Factors Potentially Influencing Carcinogen Exposure

  • Jakobsen, Jarle;Babigumira, Ronnie;Danielsen, Marie;Grimsrud, Tom K.;Olsen, Raymond;Rosting, Cecilie;Veierod, Marit B.;Kjaerheim, Kristina
    • Safety and Health at Work
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    • v.11 no.4
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    • pp.509-516
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    • 2020
  • Background: Meta-analyses have shown firefighters to be at an increased risk of several cancer types. Occupational carcinogen exposure may explain these increased risks. This study aims to describe Norwegian fire departments' work conditions from 1950 until today, focusing on factors relevant for potential occupational carcinogen exposure. Methods: With the help of a reference group, we developed a questionnaire on topics related to occupational exposure to carcinogens for the period 1950-2018. Selected Norwegian fire departments provided department-specific responses. Results: Sixteen departments, providing fire services for 48% of the Norwegian population as of 2019 and mainly consisting of professional firefighters, responded to our questionnaire. The introduction of synthetic firefighting foams, more regular live fire training, the introduction of chemical diving, and a higher number of diesel-driven fire service vehicles were identified as changes thought to increase exposure to occupational carcinogens. Changes thought to decrease exposure included the switch from negative to positive pressure self-contained breathing apparatuses, the use of self-contained breathing apparatuses during all phases of firefighting, the use of ventilating fans during firefighting, increased attention to flammable materials used during live fire training, increased attention to handling and cleaning of turnout gear and other equipment, and installment of exhaust removal systems in apparatus bays. Conclusion: Norwegian fire departments' work conditions have seen several changes since 1950, and this could influence firefighters' occupational carcinogen exposure. A peak of carcinogen exposure may have occurred in the 1970s and 1980s before recent changes have reduced exposure.

Overview of the Effect of Catalyst Formulation and Exhaust Gas Compositions on Soot Oxidation In DPF

  • Choi Byung Chul;FOSTER D.E.
    • Journal of Mechanical Science and Technology
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    • v.20 no.1
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    • pp.1-12
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    • 2006
  • This work reviews the effects of catalyst formulation and exhaust gas composition on soot oxidation in CDPF (Catalytic Diesel Particulate Filter). DOC's (Diesel Oxidation Catalysts) have been loaded with Pt catalyst (Pt/$Al_{2}O_3$) for reduction of HC and CO. Recent CDPF's are coated with the Pt catalyst as well as additives like Mo, V, Ce, Co, Fe, La, Au, or Zr for the promotion of soot oxidation. Alkali (K, Na, Cs, Li) doping of metal catalyst tends to increase the activity of the catalysts in soot combustion. Effects of coexistence components are very important in the catalytic reaction of the soot. The soot oxidation rate of a few catalysts are improved by water vapor and NOx in the ambient. There are only a few reports available on the mechanism of the PM (particulate matter) oxidation on the catalysts. The mechanism of PM oxidation in the catalytic systems that meet new emission regulations of diesel engines has yet to be investigated. Future research will focus on catalysts that can not only oxidize PM at low temperature, but also reduce NOx, continuously self-cleaning diesel particulate filters, and selective catalysts for NOx reduction.

Self-cleaning Surface Coatings of Perfluorinated Additives with Resin and Their Surface Properties

  • Kim, Y.W.;Chung, K.;Lee, E.A.;Seo, Y.G.
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 2002.10b
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    • pp.143-144
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    • 2002
  • A series of alcohols with perfluorinated segments $F(CF_2)_m(CH_2)_n-OH$, with m=8, 10 and n=4, 6, 10, were synthesized. First, the alcohols were reacted with fatty acid to produce several esters $(F(CF_2)_m(CH_2)-OOC-R$ with m=8, 10 and n=2, 4, 8,) containing perfluoro group by condensation reaction, and characterized by FT-IR, GC, and surface tension. The esters were soluble in ethyl ether, toluene, hexane, ethyl acetate, chloroform, and acetone, but insoluble in methyl alcohol, ethyl alcohol and isopropyl alcohol. Preliminary experiments on 1,2-dichloroethane solutions showed a remarkable decrease of surface tension upon addition of the esters. Also, the esters films ranged from 100 to $122^{\circ}$, depending on the structure of fatty acid esters. As the separate experiment, the water-repellency of coated paper and cotton was evaluated. As a result, the water droplet dropped in surface was not permeated for two weeks.

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Desalination of geothermal water by membrane distillation

  • Gryta, M.;Palczynski, M.
    • Membrane and Water Treatment
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    • v.2 no.3
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    • pp.147-158
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    • 2011
  • Membrane distillation process was used for desalination of hot (333 K) geothermal water, which was applied in the plant producing heating water. The investigated water contained 120 g salts/$dm^3$, mainly NaCl. The mineral composition was studied using an ion chromatography method. The obtained rejection of solutes was closed to 100%, but the small amounts of $NH_3$ also diffused through the membrane together with water vapour. However, the composition of obtained distillate allowed to use it as a makeup water in the heating water system. The geothermal water under study was concentrated from 120 to 286 g NaCl/$dm^3$. This increase in the solution concentration caused the permeate flux decline by a 10-20%. The geothermal water contained sulphates, which was subjected to two-fold concentration to achieve the concentration 2.4-2.6 g $SO{_4}{^{2-}}/dm^3$ and the sulphates then crystallized in the form of calcium sulphate. As a results, an intensive membranes scaling and the permeate flux decline was observed. The XRD analysis indicated that beside the gypsum also the NaCl crystallites were deposited on the membrane surfaces. The fresh geothermal water dissolved the mixed $CaSO_4$ and NaCl deposit from the membrane surface. This property can be utilized for self-cleaning of MD modules. Using a batch feeding of MD installation, the concentration of geothermal water was carried out over 800 h, without significant performance losses.

Epicuticular Waxes and Stomata of Adult Scale Leaves of the Chinese Juniper Juniperus chinensis

  • Kim, Ki-Woo
    • Applied Microscopy
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    • v.42 no.3
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    • pp.124-128
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    • 2012
  • Leaf surface structures were investigated in the Chinese juniper Juniperus chinensis by scanning electron microscopy. Adult scale leaves were collected from the tree, air-dried at room temperature, and sputter-coated with gold without further specimen preparation. Approximately fi ve stomata were locally distributed and arranged in clusters on the leaf surface. Stomata were ovoid and ca. 40 ${\mu}m$ long. The epicuticular wax structures of J. chinensis leaves were tubules and platelets. Numerous tubules were evident on the leaf regions where stomata were found. The tubules were cylindrical, straight, and ca. 1 ${\mu}m$ in length. They almost clothed the stomatal guard cells, and occluded the slit-shaped stomatal apertures. Moreover, the wax ridges were flat crystalloids that were connected to the surface by their narrow side. They did not have distinct edges, and their width/height ratio varied. In particular, the wax ridges could be discerned on the leaf regions where stomata were not present nearby. Since the wax ridges did not have distinct edges on their margin, they were identified as platelets. Instances were noted where platelets were oriented either parallel to each other or perpendicular to the cuticle surface. These results can be used in biomimetics to design the hierarchical structures for mimicking the plant innate properties such as hydrophobicity and self-cleaning effects of the leaf surface.

The assessment of self cleaning velocity and optimal flushing velocity in water distribution system (상수관망의 자가세척 유속과 적정 플러싱 유속 평가)

  • Bae, Cheol-Ho;Choi, Doo Yong;Kim, Ju-Hwan;Kim, Do-Hwan
    • Journal of Korean Society of Water and Wastewater
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    • v.28 no.4
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    • pp.441-451
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    • 2014
  • The flushing is important to maintain good water quality in water main. It is a technique of using water velocity to remove sediments in water distribution system. The variety of water quality problems can occur in a distribution system, so too can a variety of benefits be gained by system flushing. In order to effectively perform the flushing, the contaminants to be removed to set up and it can be solved, it is necessary to ensure the proper flow rate. In this study, the removal of contaminants present in the inner water pipe attached loose deposits such as fine particles of granular activated carbon, sand and iron corrosion product sought to derive flow rates. Thus, the constant observation of using pilot plant scale water distribution plant for the movement of floating characteristics of particles were assessed.