• Title/Summary/Keyword: Covering materials

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Budbreak, Floral Bud and Fruit Characteristics of Kiwifruit as Affected by Various Windbreaks (파풍망 종류에 따른 키위의 발아, 개화 및 과실 특성)

  • Kwack, Yong-Bum;Kim, Hong Lim;Lee, Mockhee;Rhee, Han-Cheol;Kwak, Youn-Sig;Lee, Yong Bok
    • Korean Journal of Environmental Agriculture
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    • v.36 no.3
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    • pp.169-174
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    • 2017
  • BACKGROUND:Kiwifruit growers build their vineyards using many windbreaks to protect their kiwifruit vines from defoliation injury by strong winds such as typhoon. In this study, we have compared fruit quality, budbreak rate and floral bud as affected by windbreaks. And also we surveyed several microclimate indices of kiwifruit orchard depending on the covering materials of arch-type windbreaks. METHODS AND RESULTS: Five different windbreak materials including polyethylene film (PE), blue- and white-colored nets were tested in pipe-framed archtype kiwifruit vineyards as the covering materials. Photosynthetically active radiation (PAR), annual mean temperature (AMT) and chill unit (CU) as well as fruit quality were compared among the covering materials. In all treatments, annual PAR was more than $400{\mu}mol\;m^{-2}s^{-1}$, in which kiwifruit leaf could reach its maximum photosynthesis, since the leaves were emerged. Annual mean temperature was greater in 0.1 mm-PE covering as much as $1-2^{\circ}C$ than other windbreaks. In CU calculated by three different models, all windbreaks showed more than 1400 CU that is fully fulfilled CU for kiwifruit rest completion. There were no difference in budbreak rate among the covering materials. Fruit weight was heavier in 0.1 mm-PE and white-net (4 mm) than other windbreaks. CONCLUSION: Regardless of the windbreak materials, the PAR quantity was enough for kiwifruit photosynthesis. And CU for kiwifruit rest completion was fully achieved in all treatments. However, with respect to fruit weight, quantity of PAR, and AMT, etc., It is highly recommended for kiwifruit growers to choose 0.1 mm-PE and white-net (4 mm) as for their windbreaks materials.

An Experimental Study on the Corrosion Characteristics of Reinforcement Concrete According to Types of Surface Covering Material (표면피복재 종류에 따른 철근콘크리트의 철근 부식특성에 관한 실험적 연구)

  • 김갑수;장종호;김재환;김용로;오시덕;김무한
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2003.05a
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    • pp.39-43
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    • 2003
  • Chloride ions are considered to be the major cause of steel corrosion in concrete structures exposed to seashore environments and also permeation of chloride is controlled by chloride diffusion. Therefore, the study on chloride diffusion of concrete have been done so far by many researchers. It is reported that coating material as surface covering material is effect about deterioration of salt damage and carbonation, therefore these materials are important in durability of concrete structure. In this study, corrosion characteristics of reinforcement concrete according to types of surface covering material were evaluated by water-cement ratio, chloride penetration by age on the corrosion area rate and mass decrement of reinforcement. And it is considered that the result of this study on application of the corrosion characteristics of reinforcements under salt damage environmental will be suggested as fundamental data of control performance of salt damage. It is performed that comparison and examination of control performance of salt damage by the corrosion characteristics under salt damage environmental.

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Effect of Pelleting Treatment on Seed Germination in Adenophora triphylla (잔대 종자 펠렛처리가 종자 발아에 미치는 영향)

  • Im, Dong Hyeon;Nam, Joo Hee;Kim, Jong Hyuk;Lee, Min Ju;Rho, Il Rae
    • Korean Journal of Medicinal Crop Science
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    • v.28 no.2
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    • pp.128-135
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    • 2020
  • Background: Sowing seeds of Adenophora triphylla is known to be difficult owing to their small size and irregular seed shape. Therefore, this study was conducted to develop a seed pelleting technique to save labor during sowing. Methods and Results: To identify the optimal germination temperature for A. triphylla seeds, the temperature range was set from 17℃ to 32℃. Germination surveys were conducted in plastic greenhouse conditions in March, April, and May to determine the appropriate sowing time. The optimal germination temperature for A. triphylla seeds was 29℃ and May was the optimal sowing time in plastic greenhouse conditions. Covering materials for seed pelleting used talc (T), kaolin (K), calcium carbonate (C), and vermiculite (V). The pellet binder used agar (A), pectin, xanthan gum, polyvinyl alcohol (PVA), and sodium alginate (S). The best suited treatment mixture were the best suited in kaolin / calcium carbonate / vermiculite (KCV), talc / calcium carbonate / vermiculite (TCV) mixture treatment for covering material, and sodium alginate (S), agar (A) as pellet binder, respectively. The germination rate was the best in TCV mixed with S. Conclusion: The mixture of TCV (2 : 1 : 3) + 1.5% S (TCVS), was found to be the best pelleting materials for A. triphylla seeds, and seed pelleting can be labor-saving during sowing.

Study on pH Reducing Method of Recycled Fine Aggregate for Embanking or Covering (성복토용 순환잔골재의 pH 저감방법에 관한 연구)

  • Han, Min-Cheol;Han, Dongyeop
    • Journal of the Korea Institute of Building Construction
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    • v.17 no.1
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    • pp.23-30
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    • 2017
  • The aim of the research is to suggest an economical and sustainable method of reducing pH of recycled aggregate as an embanking and a covering materials. Because of the unhydrated cement based materials on the surface of the recycled aggregate, it causes a severe problem on environment with leaked high alkali water from embankment and covering by using recycled aggregate. In this research, to reduce the pH of recycled aggregate, regarding the recycled fine aggregate, eight different methods were tested and analyzed with three different categorized: natural treatment, artificial treatment, and chemical treatment. From the results of experiment, it was considered that the most efficient method of reducing pH of recycled aggregate was the chemical treatment using acid such as $CO_2$ acceleration or monoammonium phosphate (MAP), and diammonium phosphate (DAP). Especially, using MAP and DAP, fertilizers, is the most efficient method of reducing pH with its time duration and performance.

Analytical Beam Field Modeling Applied to Transducer Optimization and Inspection Simulation in Ultrasonic Nondestructive Testing

  • Spies, Martin
    • Journal of the Korean Society for Nondestructive Testing
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    • v.23 no.6
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    • pp.635-644
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    • 2003
  • To ensure the reliability of ultrasonic nondestructive testing techniques for modern structural materials, the effects of anisotropy and inhomogeneity and the influence of non-planar component geometries on ultrasonic wave propagation have to be taken into account. In this article, fundamentals and applications of two analytical approaches to three-dimensional elastic beam field calculation are presented. Results for both isotropic materials including curved interfaces and for anisotropic media like composites are presented, covering field profiles for various types of transducers and the modeling of time-dependent rf-signals.

A Study on the Urethane Foam Material Characteristics and Appropriate Soil Covering for Mine Reclamation Emergency Action through Atificial Fire Test (인공 화재 실험을 통한 광해방지 응급조치용 우레탄 폼 재료 특성 및 적정 복토에 관한 연구)

  • Kim, Soo Lo;Park, Jay Hyun;Lee, Jin Soo;Yang, In Jae
    • Economic and Environmental Geology
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    • v.53 no.3
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    • pp.287-296
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    • 2020
  • Mine Reclamation Project is being carried out with the aim of ensuring a sustainable green living and helping to develop eco-friendly mines by analyzing, removing and preventing the harmful factors. Mines developed during the japanese colonial period and mining boom period are still not repaired throughout the country, and from these scattered risks, public safety is worth pursuing as a top priority. The project that is close to public safety in the mine recalmation project is an emergency treatment, and the most widely used method is a filling method similar to the ground subsidence prevention. If dangerous mine cavity or tunnels are located in the mountains, charging with existing materials may not be possible, or unreasonable cases may occur, and new methods of technological development are required. Emergency actions should be carried out safely and efficiently to prevent the loss of precious people's lives on the hiking paths adjacent to dangerous mining sites. In these field conditions, urethane foam materials may be an alternative. In this study, the applicability of urethane foam materials in mining was reviewed through overseas cases. It was also tested on the appropriate depth of top soil for the protection of urethane foam materials through forest fire simulation test. The test result show that approximately 15cm of soil covering (recommended 20cm over) was suitable for maintaining the function of foam materials from forest fires.

안정화 층에 따른 YBCO 박막형 선재의 통전 특성에 관한 연구

  • Du, Ho-Ik;Kim, Min-Ju;Kim, Yong-Jin;Lee, Dong-Hyeok;Han, Byeong-Seong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.11a
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    • pp.214-214
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    • 2009
  • While critical properties of BSCCO wires rely considerably on grid direction upon BSCCO and have very complicated mechanism of generating a superconducting phase, making it difficult to improve properties of wires, YBCO thin-film wires which can be formed in a superconducting phase upon metal board through vapor deposition processing can get excellent direction and reduce manufacturing costs with more flexibility in improving critical properties; thus, they will be suitable for instrument application in the future. Contrary to BSCCO wires for which thick silver alloy covering materials should inevitably be used, moreover, YBCO thin-film wires have an advantage of making thickness and quality of covering materials different by usage. Such a property can be an important element to widen application of wires by presenting possibility of using thin-film wires as superconducting material for fault current limiter as well as for high power current application. In this study we intend to prepare YBCO thin-film wires with different stabilizer layers to analyze current application and current restriction properties by stabilizer layers on the basis of detailed researches on changes in current classification properties below critical value.

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Synthesis and Characterization of Artificial Skin based on Polypeptides (Polypeptide계 인공 피부의 합성과 특성)

  • Kim, Seon-Jeong;Min, Dong-Seon;Kim, Gye-Yong
    • Journal of Biomedical Engineering Research
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    • v.8 no.1
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    • pp.87-92
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    • 1987
  • In order to evaluate the artificial skin for burn would covering materials, copoly(N. carbobenzoxy-L-Iysine-L-leucine)s were prepared by Ipolymerization of N - carbobenzoxy-L- I sine anhydride and L-leucine anhydride in homogeneous solvents using triethylamine as an initiator. The synthetic polypeptides and the oxter type polyurethane(PV)of medical grade were used as the sheet type membranes were prepared ; monolayer membrances were composed of only the polypeptides, bilayer membranes and blend membranes were controlled by composition of the polypeptides and PU. Test of the swelling degree, mechanical tensile strength, elongation, oxygen permeability, water-vapor loss and In vitro degradation treated by pretense TV of samples of artificial skin were measured by adequate methods so as to mechanical, physincal characterization and biodegradation. As a result, all the values of samples were found to be similar to desired value of skin which was nature. The Artificial skin based on polypeptides can be considered as ideal burn wound covering materials.

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