• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2000.11a
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• pp.65-68
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• 2000

Polyethylene, has long history and is widely used, was researched due to good electrical properties by many authors. But PE under stress has the critical defects of space charge accumulation and tree growth, so various methods such as catalyst, additives and blend to improve these problems have been execute, of which we selected blending method. As in our previous papers we investigated electrical conduction, dielectric and AC dielectric breakdown characteristics, we did DC dielectric breakdown characteristics in this paper. We selected pure LLDPE, pure EVA and LLDPE films mixed with EVA as specimens, which were mixed with the weight percentages of 50, 60, 70 and 80[wt%] to be thin film. DC applying voltage speed was 500[V/sec]. The relation between dielectric breakdown characteristics and the variations of super structure due to mixing was investigated, and especially trap level at amorphous region, threshold energy increment of conductive electron at free volume were considered.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.10a
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• pp.99-100
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• 2001

창란젓갈은 명태의 내장을 원재료로 만든 젓갈로서 자가소화효소나 미생물의 초기 오염도가 높고, 특히 저염양념젓갈은 다른 젓갈에 비해 변패가 빠른 편이며, 냉장조건에서도 유통기한이 40일 정도로 짧아, 콜드체인시스템을 잘 지키지 않는 국내 유통 특성상 고온의 외기에 제품이 노출될 기회가 많아 반품발생률이 증가하는 실정이다. 창란젓갈을 비롯한 젓갈류는 대부분 병포장이나 필름포장인 PE(low density polyethylene)를 사용하고 있는데, 병포장한 창란젓갈의 문제점은 압력이 증가할 경우 내부에 기포가 형성되어 냄새나 액즙이 누설되고 심하면 포장이 파손되기도 하고, 가물은 소비자가 병 뚜껑을 개방할 때 파열음과 함께 내용물이 유출되는 등 상품성이 저하되는 경향이 있다. (중략)

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2003.10a
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• pp.196-199
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• 2003

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.11a
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• pp.65-68
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• 2000

Polyethylene, has long history and is widely used, was researched due to good electrical properties by many authors. But PE under stress has the critical defects of space charge accumulation and tree growth, so various methods such as catalyst, additives and blend to improve these problems have been execute, of which we selected blending method. As in our previous papers we investigated electrical conduction, dielectric and AC dielectric breakdown characteristics, we did DC dielectric breakdown characteristics in this paper. We selected pure LLDPE, pure EVA and LLDPE films mixed with EVA as specimens, which were mixed with the weight percentages of 50, 60, 70 and 80[wt%] to be thin film. DC applying voltage speed was 500[V/sec]. The relation between dielectric breakdown characteristics and the variations of super structure due to mixing was investigated, and especially trap level at amorphous region, threshold energy increment of conductive electron at free volume were considered.

• Korean Journal of Food Science and Technology
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• v.14 no.2
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• pp.156-161
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• 1982

Three plastic film solar dryers covered with different film layer were constructed by modifying farm vinyl house and studied their performance. The collection efficiency and temperature raising of type C which was covered with double layers of transparent PE and black PVC film was most efficient, followed after B covered with double layer of transparent PE film and type A covered with single layer transparent PE film. The inside temperature of type C was average $18^{\circ}C$ higher than ambient temperature and its collection efficiency showed 31.5% with air flow rate of $3.8m^3/min$. The solar energy collection efficiency of type C was increased in proportion to air flow rate up to 60.2% at $11.3m^3/min$. In demonstration drying test of red pepper in type C, drying capacity per unit area was 2.5 times higher than that of conventional solar drying on straw mat and drying time shortened to about half.

• Journal of Mushroom
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• v.22 no.1
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• pp.31-36
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• 2024

Plastics are widely used in industries in human society and because of their structural stability, degradation is a serious global issue. To estimate the degradation of plastic, 31 edible mushrooms were cultured with the selected plastic films (polyethylene [PE], polystyrene [PS], and poly(ethylene terephthalate) [PET]) for 3 months at 25 ℃. Measuring the weight of the films showed that four species of mushrooms, namely Porostereum spadiceum, Ganoderma lucidum, Coprinellus micaceus, and Pleurotus ostreatus, exhibited the highest degrees of plastic degradation. In addition, the mushrooms and fungi that exhibited the most significant plastic degradation were cross-cultured to promote this degradation. As a result, cross-cultivation of G. lucidum and Aspergillus niger showed a weight loss of 2.49% for the PET film. For the PS film, Aspergillus nidulans showed a weight loss of 4.06%. Cross-cultivation of A. nidulans and C. micaceus, which showed a weight loss of 2.95%, was noted as an alternative for PS biodegradation, but is harmful to humans. These bio-degradation effects of edible mushroom will contribute to the development of alternatives for eco-friendly plastic degradation.

• Food Science and Preservation
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• v.12 no.5
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• pp.424-431
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• 2005

'Hongro' and 'Gamhong' apples grown at the Gochang-si in the southern part of Korea were harvested on September in 2002 for storage study. Each cultivar was divided into two groups of maturity based on the harvested date. Immature fruits were harvested 10 days early compared to fruits having proper maturity. This study was conducted to evaluate quality the change of 'Hongro' and 'Gamhong' apples newly bred by different storage methods with PE film package and CA conditions. A typical climacteric respiration pattern was observed in new variety 'Hongro' and 'Gamhong' apples stored at room temperature. The results indicated that fresh quality of the stored fruits in CA condition was better than that in other treatments during storage. Qualities of apples were least changed at CA storage of 3% $CO_2$ and 1% $O_2$. CA storage was effective in maintaining the freshness of 'Hongro' and 'Gamhong' for 16 weeks.

• Korean journal of food and cookery science
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• v.24 no.4
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• pp.480-486
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• 2008

In this study, Yukwa(YU-G) was prepared by coating in syrup with water-soluble extracts of Gugija(Lycii fructus). The Yukwa samples were stored with PE film packing with air for 12 weeks at room temperature, after which the quality and shelf-life of the Yukwa were assessed. During storage, the moisture contents of YU-G were higher than those of the Yukwa due to being coated in syrup without water-soluble extracts of Gugija(YU-NG), whereas the instrumental textural hardness values of the YU-G were lower than those of the YU-NG. Color determination indicated that YU-NG and YU-G assumed a darker color after storage, becoming both redder and yellower. The peroxide and acid values increased abruptly in the YU-NG during storage, but increased slowly in the YU-G. During the 12 weeks of storage after preparation, the peroxide and acid values of YU-G remained at less than 40 meq/kg and 4 KOH mg/g, respectively. Thus, the experimental method of syrup coating with water-soluble extracts of Gugija rendered the YU-G fairly stable against fat rancidity. The YU-G evidenced generally higher overall acceptability than YU-NG when stored.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.823-828
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• 2005

To lower the calories of buckwheat noodle, which is good for reducing obesity and for Preventing adult disease, glucomannan and flour containing resistant starch(RS) were used during the noodle making Process. Compared with raw noodle, this buckwheat raw noodle had $30\%$ fewer calories. This low caloric buckwheat noodle was coated with olive oil which is reputed as well-being food to prevent soddening to make instant type buckwheat noodle. Its shelf-life was extended to 90 days under normal temperature($35^{\circ}C$I). Among four noodle samples with different combinations of raw materials, the best was made of flour with RS formula flour, buckwheat flour, glucomannan, activated gluten, and emulsifying agent. The one without salt had better quality. Among 6 kinds of packing materials, OPP/Al/PE composite level film demonstrated the best quality packing materials.

• Membrane Journal
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• v.32 no.1
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• pp.57-65
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• 2022

Recently, computer simulation research has been rapidly increasing due to the development of computer and software technology. In particular, various computational simulation results related to polymers, which were previously limited by problems of the number of atoms and model size, are being published. In this study, a study was conducted to analyze the mechanical properties, one of the important properties for using a polymer material as a membrane, using molecular dynamics (MD) simulation. To this end, polyethylene (PE) and polystyrene (PS), which are commercial polymer materials with widely reported related properties, were selected as polymer models and the tensile properties of each polymer were compared through the difference in main chain length. Through the density, radius of gyration, and scattering analysis, it was found that the model produced in this study was in good agreement with the mechanical property trends obtained in the actual experiment. It is expected to enable the prediction of mechanical properties of various polymer materials for membrane fabrication.