• Title/Summary/Keyword: Covering Material

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Effect of Different Irrigation Period on the Growth of Greenary Sedum Mat (삽목을 이용한 녹화용 Sedum 매트의 관수 간격에 따른 생육 특성)

  • Lee, Jong-Suk;Kim, Ji-Yeon;Yoon, So-Jeong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.10 no.2
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    • pp.54-60
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    • 2007
  • This study was conducted to investigate growth characteristics of irrigation period of greenary mats focused on management as a material to apply on rooftop. Using Sedum kamtschaticum, Sedum takesimense, Sedum reflexum, Sedum album and Sedum burrito greenary mats were made. The irrigation periods were every 3 days, 7 days, and 10 days after made each greenary mats.1. All treatments on survival ratio of 5 Sedum species were over 96%. Especially, new individuals were emerged from naturally detached leaves. 2. Growth of S. kamtschaticum, S. takesimense, S. reflexum were good on 7 day irrigation treatment. 3. The highest covering ratio of S. burrito was 3 day irrigation treatment, and the hightest of the others were 7 day irrigation treatment. Considerations for species selection, mixture, ratio and management were obtained from this study.

The Use of Water Treatment Sludge as a Landfill Cover Material (정수장(淨水場) 슬러지의 매립장(埋立場) 복토재(覆土材)로의 활용(活用)에 관(關)한 연구(硏究))

  • Lee, Kee-chool;Oh, Joon-seong
    • Clean Technology
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    • v.8 no.2
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    • pp.67-76
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    • 2002
  • Dewatered sludge of 400,000t/y from water treatment plants in Korea is being disposed through landfill and ocean dumping. However, the disposal is posing more and more serious environmental problems at the same time not only because of landfill site shortage in municipal suburbs, but because of the concern it will contaminate the oceans. In this study, the research on utilizing the sludge dried by flash dryer as covering soil in the landfill sites was carried out to solve these problems on environmental affinity. Both dewatered and dried sludge were exposed to the natural condition and observed according to the atmospheric changes. An experiment of soil engineering characteristics of the dried sludge and tests on mixed sludge(silty sandy soil : dried sludge = 10:90 ~ 30:70) such as particle size distribution, liquid and plastic limit, moisture content, specific gravity and compaction test were carried out. According to the compaction test, the compaction was confirmed as the optimum water content ratio was observed in the condition of SM-silty sand of particle size distribution, NP of liquid and plastic limit, 101.4% of moisture content, 2.04~2.12 of specific gravity. The results showed that dried sludges mixed with at least 30% of natural soil could be used as daily covering soil in the landfill sites.

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Effect of Polycarbonate Covering Sheet on Greenhouse Indoor Environments and Growth Behavior of Cherry Tomatoes

  • Choi, Kyung Yun;Kim, Soo Bok;Bae, Seokhu;Yoon, Jeong-Hwan;Yun, Ju-Ho;Kim, Namil
    • Elastomers and Composites
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    • v.55 no.2
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    • pp.114-119
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    • 2020
  • The effect of a greenhouse-covering material on its indoor environment and on the characteristics of cherry tomatoes grown in it was investigated. The conventional polyethylene (PE) film on the greenhouse roof was replaced by a polycarbonate (PC) sheet, while maintaining the main structural frame intact. Color changes and the formation of water droplets on the PC surface were avoided by applying coextrusion and coating layers. When compared to the PE greenhouse, the PC greenhouse enabled increased light transmittance and thus a higher indoor temperature during both summer and winter. The thermal insulating property of the PC sheet effectively reduced the heating loss by approximately 55% during winter. The cherry tomatoes grown in the PC greenhouse exhibited superior fruit characteristics in terms of size, weight, and sugar content. The total amount of cherry tomatoes produced per unit area (1,000 ㎡) in the PC greenhouse was found to be greater by approximately 19% compared to that in the PE greenhouse.

A Study on Chipogwan (치포관(緇布冠) 연구)

  • Park, Kill-Su;Choi, Kyu-Soon
    • Journal of the Korean Society of Costume
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    • v.61 no.5
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    • pp.123-138
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    • 2011
  • This study examined how Chipogwan[緇布冠] with such a long history has been changed in China and Korea. With regard to the name, material, use and form of Chipogwan, the results of this study is summarized as follows. Chipogwan was mentioned continuously in ancient books of ceremonies and literature from the Tang dynasty [唐代], but from the Song dynasty [宋代] new name Chigwan [緇冠: a black hat] appeared besides Chipogwan. The two names were transmitted to Joseon dynasty [朝鮮] and used together until the mid Joseon dynasty, but from the 18th-19th centuries, Chipogwan was adopted according to ancient ceremonies and this name has been used continuously until today. The change of the name reflects the change of the material. Ancient Chipogwan was made of hemp [布] but when the term Chigwan appeared in the Song dynasty it was made of paper and Sa [紗: a 2-end simple gauze]. As other materials were added to hemp, po (布) was omitted from Chipogwan. As to the use of Chipogwan, it was a coronet used in purification ceremonies [齋冠] in ancient times. Then, it was used as Chogagwan [初加冠: a first hat putting on] in coming-of-age ceremonies [冠禮] from Zhou dynasty (周). During the Song and Joseon dynasty, Chipogwan was used in coming-of-age ceremonies as well as in daily life. As to the form, Chipogwan in ancient books of rites and the Song dynasty was a small coronet covering the topknot. In the Joseon dynasty, the form of Song dynasty was followed until the mid period, and then after the mid $18^{th}$ century, another form was proposed according ancient books of rites and an independent form of ceremonial coronet appeared that covered the entire head rather than covering only the topknot.

Onlay Rib Bone Graft in Elevation of Reconstructed Auricle: 17 Years of Experience

  • Kim, Taehoon;Han, Jihyeon;Lee, Yoonho
    • Archives of Plastic Surgery
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    • v.40 no.3
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    • pp.209-213
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    • 2013
  • Background A cartilage wedge block and covering flap are standard procedures for firm elevation of the ear in microtia correction. However, using costal cartilage for elevation of the reconstructed auricle can be insufficient, and the fixed cartilage wedge block may be absorbed or may slip out. Furthermore, elevating covering flaps is time-consuming and uses up fascia, a potential source of reconstruction material. Therefore, we propose an innovative method using autologous onlay rib bone graft for auricular elevation of microtia. Methods From February 1995 to August 2012, 77 patients received a first stage operation with a rib cartilage framework graft. In the second stage operation, a small full thickness of rib bone was harvested through the previous donor scar. The bihalved rib bone was inserted into the subperiosteal pocket beneath the cartilage framework. Results The follow-up time ranged from 1 month to 17 years, with a mean of 3 years. All of the patients sustained the elevation of their ears very well during the follow-up period. Donor site problems, except for hypertrophic scars, were not observed. Surgery-related complications, specifically skin necrosis, infection, or hematoma, occurred in 4 cases. Conclusions Onlay rib bone graft used to elevate the reconstructed auricle is a more anatomically appropriate material than cartilage, due to the bone-to-bone contact between the bone graft and the temporal bone. Postoperative minor correction of the elevation degree is straightforward and the skin graft survives better. Therefore, reconstructed auricle elevation using onlay rib bone graft is a useful and valuable method.

Characteristics in the Lingerie Looks Designed by John Galliano (John Galliano 작품에 나타난 란제리룩의 특성)

  • Kim, Sun Young
    • Journal of the Korean Home Economics Association
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    • v.51 no.2
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    • pp.147-159
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    • 2013
  • This study aims at developing and producing the creative design of a lingerie look after reviewing the aesthetic value about lingerie look featured in John Galliano's works. As for the research method, the selection process from the works was followed together with literature review for empirical analysis over lingerie looks, where 2,764 pieces in total were reviewed from Galliano's Pret-a-Porter collections covering from 2001S/S until 2010F/W and Christian Dior's Haute Couture and Pret-a-Porter collections that he is in charge of as head designer and 291 pieces were finally singled out that show the lingerie look image well. Then, the formative expression was examined about those looks and the characteristics were induced from them. Formativeness expressed in Galliano's lingerie look, in term of lingerie style, was categorized as erotic, retro, and deconstructive. The glittering and smooth material like silk and satin, and the visible material like lace and chiffon were mainly used for material rather than foreign material. By doing so, the romantic and erotic image was highlighted. In the production method, it was grouped into transposition of wear, direct and indirect exposition, and deconstructive way. These aesthetic characteristics introduced by formative expression appeared in the form of eroticism, play, and deconstructiveness.

Novel nonlinear stiffness parameters and constitutive curves for concrete

  • Al-Rousan, Rajai Z.;Alhassan, Mohammed A.;Hejazi, Moheldeen A.
    • Computers and Concrete
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    • v.22 no.6
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    • pp.539-550
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    • 2018
  • Concrete is highly non-linear material which is originating from the transition zone in the form of micro-cracks, governs material response under various loadings. In this paper, the constitutive models published by many researchers have been used to generate novel stiffness parameters and constitutive curves for concrete. Following such linear material formulations, where the energy is conservative during the curvature, and a nonlinear contribution to the concrete has been made and investigated. In which, nonlinear concrete elastic modulus modeling has been developed that is capable-of representing concrete elasticity for grades ranging from 10 to 140 MPa. Thus, covering the grades range of concrete up to the ultra-high strength concrete, and replacing many concrete models that are valid for narrow ranges of concrete strength grades. This has been followed by the introduction of the nonlinear Hooke's law for the concrete material through the replacement of the Young constant modulus with the nonlinear modulus. In addition, the concept of concrete elasticity index (${\varphi}$) has been proposed and this factor has been introduced to account for the degradation of concrete stiffness in compression under increased loading as well as the multi-stages micro-cracking behavior of concrete under uniaxial compression. Finally, a sub-routine artificial neural network model has been developed to capture the concrete behavior that has been introduced to facilitate the prediction of concrete properties under increased loading.

SMALL-SCALE Hα DYNAMIC FEATURES SUPPORTED BY CHROMO SPHERIC MAGNETIC RECONNECTION

  • LEE SANGWOO;YUN HONG SIK;CHAE JONGCHUL;GOODE PHILIP R.
    • Journal of The Korean Astronomical Society
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    • v.36 no.spc1
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    • pp.21-27
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    • 2003
  • In the present study, we have investigated morphology and evolution of small-scale Ha dynamic features on the quiet sun by analyzing video magnetograms and high resolution Ha images simultaneously taken for 5 hours at Big Bear Solar Observatory on April 18, 1997. From comparisons between time sequential longitudinal magnetograms and H$\alpha$ images covering $150" {\times} 150"$, several small-scale H$\alpha$ dynamic features have been observed at a site of magnetic flux cancellation. A close relationship between such features and cancelling magnetic fluxes has been revealed temporarily and spatially. Our results support that material injection by chromospheric magnetic reconnect ion may be essential in supporting numerous small-scale H$\alpha$ dynamical absorption features, being in line with recent observational studies showing that material injection by chromospheric magnetic reconnect ion is essential for the formation of solar filaments.

Repair and Strengthening Method Using Near Surface Mounted FRP Rods and Overlay (FRP Rod를 이용한 표면매립 및 단면 확대 복합 보수$\cdot$보강 공법)

  • Hwang Gum-sic;Park Chin-ki;Won Jong-pil
    • Composites Research
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    • v.18 no.4
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    • pp.66-74
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    • 2005
  • This paper reports new repair and strengthening mathod using improved material. This mathod have two type according to covering thickness of reinforcement. One type is near surface mounted FRP rod. Anther type is overay. Fiber Reinforced Plastic (FRP) materials has become very popular in recent years. FRP material used to rehabilitate many types of structures with superior characteristics such as high strength and stiffness and corrosion resistance. This strengthening mathod were used FRP rod which have better bond and shear strangth than current FRP rod. Development of FRP rod due to 3-D winding system. In addition, Ductile hybrid FRP has a certain plastic deformation and an elongation greater than 3% at maximum load is usually required for steel reinforcement in concrete structures. Moerover this mathod can be effective repair of base concrete by sprayed polymer mortar.

디스크형 진동자를 이용하는 새로운 형태의 밸브리스 마이크로 압전 펌프

  • O, Jin-Heon;Im, Jong-Nam;Jeong, Ui-Hwan;Im, Gi-Jo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.91-91
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    • 2009
  • Piezoelectric micro-pump should contain the physical running parts like check valves for acquiring the unilateral motion of fluid from the alternating motion of actuators. But the check valves raise many problems such as abrasion or exhaustive destruction by the recursive mechanical displacement To solve these problems, we propose a novle type piezoelectric valveless micro-pump using peristaltic motion due to the traveling wave excitation. Proposed pump model is consisted of two piezoelectric ceramic plates, elastic metal body, caps for covering flow path, rubber rings for sealing tightly and disk springs for the pressurization of pump body.

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