• Korean journal of applied entomology
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• v.20 no.2 s.47
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• pp.83-86
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• 1981

Experiments were carried out to study on control of stem blight of asparagas caused by Shoma asparagi Sacc. in Suweon, $1976\~1978$. Symptoms of the disease were found in the field from late of May and severe infection was shown thereafter. Plastic film mulching with foliage spray of Topsin 154g a.i. and Difolatan 220g a.i. per 10a at 10days interval during the growing season, gave significantly good control and high yield compared with other treatments. In addition to reduction of the disease, the treatment with mulching has maintained good soil moisture for asparagus growth when the soil moisture was measured at about loom under the soil surface from July to August.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.1
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• pp.30-35
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• 2015

This study was conducted to investigate investigated the effect of nitrogen fertilizer on nitrate concentration in soil solution and to determine the relationship between yield and nitrate concentration in soil solution for cucumber cultivation under plastic film house. Nitrogen as urea was applied at rates of 0, 120, 240, 360, and $480kg\;N\;ha^{-1}$ as an additional fertilizer by trickle irrigation during cucumber cultivation. Monitoring of nitrate concentration in soil solution was investigated using porous cups at 25 cm depth under soil surface. Nitrate concentration in soil solution increased with increasing the rate of additional nitrogen. Correlation coefficient between EC value and nitrate concentration was positive in soil and soil solution (p<0.05). An additional nitrogen of about $300kg\;ha^{-1}$ was shown the highest yield of cucumber, and improved yield by 5% compared to N recommendation of $240kg\;N\;ha^{-1}$. The highest yield was determined at nitrate concentration of $82mg\;L^{-1}$ in soil solution by regression equation ($Y=74.2+0.73X+0.000504X^2$, $R^2=0.629^*$). These results means indicate that nitrate concentration in soil solution would be useful method to rapid determination for additional nitrogen during cucumber cultivation under plastic film house.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.700-702
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• 2005

A 5.0-inch transmissive type plastic TFT arrays were successfully fabricated on a plastic substrate at the resolution of $400{\times}3{\times}300$ lines (100ppi). All of the TFT processes were carried out below $150^{\circ}C$ on PES plastic films. After thin film deposition using PECVD, thin film failures such as film delamination and cracking often occurred. For successful growth of thin films (about 1um) without their failures, it is necessary to solve the critical problem related to the internal compressive stress (some GPa) leading to delamination at a threshold thickness value of the films. The Griffith's theory explains the failure process by looking at the excess of elastic energy inside the film, which overcomes the cohesive energy between film and substrate. To increase the above mentioned threshold thickness value there are two possibilities: (i) the improvement of the interface adhesion (for example, through surface micro-roughening and/or surface activation), and (ii) the reduction of the internal stress. In this work, reducing a-Si layer film thickness and optimizing a barrier SiNx layer have produced stable CVD films at 150oC, over PES substrates

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1455-1458
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• 2008

Amorphous silicon (a-Si:H) thin-film transistors (TFTs) are fabricated on flexible organic polymer foil substrates. As-fabricated performance, electrical bias-stability at elevated temperatures, electrical response under mechanical flexing, and prolonged mechanical stability of the TFTs are studied. TFTs made on plastic at ultra low process temperatures of $150^{\circ}C$ show initial electrical performance like TFTs made on glass but large gate-bias stress instability. An abnormal saturation of the instability against operation temperature is observed.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.27 no.3
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• pp.169-174
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• 2021

Today, plastic waste has become a critical social issue due to the increasing of plastic consumption. Korean annual per capita plastic consumption was 132 kg, the most plastic consuming country in the world. Internationally, Carbon Neutral Agreement is underway due to global warming, consumers' interest and needs for biomass-based plastics has also been increased. In this study, film was produced by adding composite use additives to the biomass-based plastics according to concentration, and the resulting changes in discharge volume, melt index, and tensile strength were investigated. Melt index (MI) was significantly higher in PLA and PBAT than in petroleum-based resin LLDPE and LDPE. Also, among the same resin or in the same treatment group, MI has been increased when the heating temperature is increased. The discharge volume and gravity of the BDP-2 to which 4% compatibilizer was added were found to be higher among all treatments, while the tensile strength of MD and TD was also higher. BDP-2 was suitable to the film producing methods for biodegradable film production.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.4
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• pp.214-223
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• 2006

For better management of micronutrients in crop cultivation, the availability of micronutrients in the soils must be updated and evaluated as a first step. This study was conducted to investigate the distribution of micronutrients in soils of plastic film houses. Total 396 soil samples were collected from the plastic film houses of various crops in Yeongnam province (strawberry, 96; red pepper, 66; tomato, 74; oriental melon, 97; cucumber, 63). Total and available contents of B, Cu, Zn, Fe, and Mn in the soils were determined. Available B was extracted with hot water and available Cu, Zn, Fe, and Mn were extracted with 0.1 N HCl. Mean values of total contents of B, Cu, Zn, Fe, and Mn in the plastic film house soils were 25, 32, 74, 21,316, and $420mg\;kg^{-1}$, respectively. Total contents of micronutrients in the plastic film house soils were similar to those found in the open fields nearby, while they were different among the locations investigated. Mean contents extractable B, Cu, and Zn in the plastic film house soils were 2.1, 7.5, and $35mg\;kg^{-1}$, respectively. The contents of extractable B, Cu, and Zn in the plastic film house soils were higher than those found in the open fields nearby with exceptions of B in soils of strawberry and Cu in soils of red pepper and oriental melon. However, mean contents of extractable Fe and Mn in the plastic film house soils were 156 and $146mg\;kg^{-1}$, respectively, and the mean content of extractable Fe was much lower than that found in open fields nearby. The contents of extractable Zn, Fe, and Mn were higher than the sufficient levels for the crop requirements in most of the plastic film house soils investigated. Contents of extractable Cu in most soils of strawberry, tomato and cucumber cultivations were higher than the sufficient level. However, extractable Cu contents were below the sufficient level in about 30% of investigated soils of red pepper and oriental melon cultivation. Soils containing higher contents of extractable B than the sufficient level were relatively fewer in comparison to the other micronutrients.

• Korean Journal of Materials Research
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• v.14 no.5
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• pp.343-347
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• 2004

We investigated the growth feasibility of polycrystalline Si film on mica substrate for the transfer of the layer to a plastic substrate. The annealing temperature was limited up to $600^{\circ}C$ because of crack development in the mica substrate. Amorphous Si film was deposited on mica substrate by PECVD and was crystallized by furnace annealing. During the annealing, bubbles were formed at the Si/mica interface. The bubble formation was avoided by the Ar-plasma treatment before amorphous Si deposition. A uniform and clean polycrystalline Si film was obtained by coating $NiCl_2$ on the amorphous Si film and annealing at $500^{\circ}C$ for 10 h. The conventional Si lithography was possible on the mica substrate and the devices fabricated on the substrate could be transferred to a plastic substrate.

• Design & Manufacturing
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• v.14 no.1
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• pp.15-21
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• 2020

Smart systems in different application areas such as automotive, medical and consumer electronics require a novel manufacturing method of electronic, optical and mechanical functions into products. Traditional methods including mechanical assembly, bonding of plastic and electronic circuit cause the problems in large size of products and complicated manufacturing processes. In this study, thermoforming and film insert molding were applied to fabricate a dome shaped plastic part embedded with electronic circuits. The deformation of patterns printed on PET film was predicted by thermoforming simulation using T-SIM, and the results were compared with those by experiment. In order to decrease spring-back after thermoforming, the Taguchi method of design of experiment was used. Through ANOVA analysis, it was found that mold temperature was the most dominant parameter for spring-back. By using flow analysis, gate design was performed to decrease injection pressure. During film insert molding, the wash-out of ink printed on film occurred for Polycarbonate. When the resin was changed to PMMA, the wash-out disappeared due to low melt temperature.

• Journal of the Korean institute of surface engineering
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• v.42 no.4
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• pp.173-178
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• 2009

DLC film was synthesized on plastic injection mold(SKD11, $30\;mm\;{\times}\;19\;mm\;{\times}\;0.5\;mm$) and Si(100) wafer for 2 h at $130^{\circ}C$ under 6 mTorr using hybrid method of rf sputtering and ion source. The obtained film was analysed by Raman spectroscopy, AFM, TEM, Nano indenter and scratch tester, etc. The film was defined as an amorphous phase. In the Raman spectrum, broad peak of $sp^2$-bonded carbon attributed to graphite at $1550\;cm^{-1}$ were observed, and the ratio of ID($sp^3$ diamond intensity)/IG($sp^2$ graphite intensity) was approximately 0.54. The adhesion of DLC film was more than 80 N with scratch tester when $0.2\;{\mu}m$ thickness Cr was coated as interlayer. The micro-hardness was distributed at 35~37 GPa. The friction coefficient was 0.02~0.07, and surface roughness(Ra) was 0.34~1.64 nm. The lifetime of DLC coated plastic injection mold using as a connector part in computer was more than 2 times of non-coated mold.

• Journal of Korean Society of Rural Planning
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• v.20 no.4
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• pp.45-54
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• 2014

The main purpose of this study is to provide the back-from-city farmers with the information about the melon cultivation technology by surveying 268 farm houses in the major melon producing districts such as Seongju and Chilgok. For the purpose, this study classifies the essential technologies that the melon experts think as most important into 6 categories: size of plastic film house, covering film, varieties of oriental melon, lagging cover, ventilation method and ways to reduce repeated-cultivation damage. The result of the study shows that the back-from-city farmers should consider the following items when they choose to cultivate oriental melons. For the size of plastic film house, the ventilation method and the covering film of plastic film house, it is better to choose the latest technology. Even though it may require larger initial investment, the latest technology can increase the production and lower the cost. In case of variety, it is better to choose popular or the most widely grown ones rather than the new ones. The lagging cover should be selected in consideration of climate conditions such as average temperature and humidity, transplant time and harvest time of the farming region.