• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.729-735
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• 2000

Moisture loss of fresh fruits and vegetables is a main cause of deterioration. It resulted not only in the direct quantitative loss, but also in change in appearance, texture and nutrition. To reduce the loss of moisture content during the distribution in the market, fresh products are packaged using plastic films. But, most of the fresh products are packaged manually in Korea. In order to minimize the labor requirement, the packaging machine for fruits and vegetables was developed and tested. Prototype was composed of film feeding unit, bag former, products feeding conveyor, film feeding roller, center sealer, end sealer and discharge conveyor. Green peppers, carrots and perilla leaves were tested with prototype. Prototype could pack 1780, 1390, 1780 bags per hour at the feeding speed of 0.08m/s respectively and 2250, 1810, 2640bags per hour at the feeding speed of 0.10m/s respectively. And packaging speed of green peppers and carrots was improved by 3.7 and 3.4 times compared with manual packaging. The packaging condition with the prototype was good and the products had almost no damages.

• Food Science and Preservation
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• v.8 no.1
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• pp.23-29
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• 2001

To extend the freshness of late autumn Chinese cabbage, the packaging and loading effects on the quality were investigated during cold storage. Judging from overall quality during storage period, late autumn Chinese cabbage could be stored by 3 months at 0$\^{C}$ cold storage. However, late autumn Chinese cabbage was not acceptable for long-term storage because of its marketability and the storage cost. Among 3 packaging methods(PP-net, carton and plastic container) for stored Chinese cabbage, plastic container and carton were more effective than PP-net packaging for the freshness prolongation. Gas composition in the plastic bags during storage was not significantly different among packaging conditions and O$_2$ and CO$_2$ concentrations were 13∼18% and 0.75∼7.48%, respectively, MAP with plastic film was effective for the quality retention because of low oxygen composition and high humidity condition in the bags.

• Journal of Korean Society for Atmospheric Environment
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• v.20 no.6
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• pp.759-771
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• 2004

This study analyzed concentrations of volatile organic compounds (VOCs) produced from incineration of plastic wastes at $600^{\circ}C$. The plastic wastes used in this study included polyethyleneterephthlate (PETE), high density polyethylene (HOPE), polyvinyl chloride (PVC), low density polyethylene (LOPE), polypropylene (PP), polystyrene (PS) and other. Plastic wastes were heated from room temperature upto $600^{\circ}C$ providing the compressed air inside of a small-scale electric furnace for 90 minutes and then they were oxidized (incinerated) for 60 minutes at $600^{\circ}C$ maintaining the same air supply. VOCs emitted from the incineration process were sampled using an air sampling pump and Tedlar air bags for 150 minutes and then the components and concentrations of the VOCs were analyzed by a GC-MS. The most prominent chemical structure of the VOCs obtained from the incineration process of the HOPE, LOPE and PP, which include ethylene groups in their main chains, was identified as aliphatic hydrocarbons such as 1-hexene. However, aromatics such as benzene were major chemical structure from the incineration of PETE, PVC and PS which include benzene rings in their main chains. This study estimated the total VOC production from the incineration of the plastic wastes based on the real plastic waste production and the emission factors. 64% and 27% of the total VOC emissions consisted of aliphatic hydrocarbons and aromatics, respectively, which have double bonds within their molecular structure and thus a high ground level ozone formation potential.

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.385-392
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• 2019

Currently, plastic bags are being used for sawdust cultivation of shiitake mushroom. However, due to serious environmental problems caused by the use of plastic bags, we studied the efficacy of bottle cultivation method to replace the sawdust bag method. Small detachable plastic bottles (400 g capacity) filled with Quercus spp. sawdust and wheat bran (4:1 w/w) media were incubated for 80 and 120 days. The weight loss (%) of the media was higher for the NIFoS 2464 strain at an approximate light intensity of 300 Lux than light intensity of 500 Lux; the light intensity was associated with the loss of sawdust medium-weight during the cultivation period. The highest yield was observed when the strain was cultivated for 80 days under dark conditions, 40 days under 500 Lux light, and air circulation fan speed of 30 rpm. When incubated for 120 days, mushroom yield in the bottle media was higher at 40 days of light exposure than 20 days of light exposure. In the bottle media incubated for 80 days under dark conditions, the mushrooms fruited due to repetitive water spraying on the top of the media and light stimulation during the fruiting period. The media could be separated from the bottles because the media shrank after the first harvest. These separated plastic bottles could be re-used for mushroom cultivation, thereby reducing the amount of plastic waste.

• Journal of Environmental Health Sciences
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• v.43 no.2
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• pp.95-102
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• 2017

Objectives: This study was conducted to evaluate the emission of VOCs from clothing that had been dry cleaned. Methods: In order to ensure the same conditions, f100% wool scarves were selected as the fabric type. Four identical tests were conducted on the option of either removing the plastic bags which came from the dry cleaning shop or not. The scarf was located inside a closet or room for one or two days. Small chamber tests were conducted to determine the VOC emission characteristics under the same conditions such as temperature, humidity, loading factor, and air exchange rates. Air from the chamber for VOCs was sampled by Tenax TA tube and analyzed by thermal desorption and GC/MSD. Results: Assuming that test represented dry cleaning and consumer's conditions well enough, we can conclude that immediate emissions after the dry cleaning of the scarfs caused elevated levels of TVOC, five VOCs (benzene, toluene, ethylbenzene, xylene, stylene), and decane group compounds. Conclusions: By removing the plastic bags which came from the dry cleaning shop or not, the storage conditions of dry cleaned scarfs by consumers during the storage time periods (one to three days) would be significant for reducing VOC emissions.

• Korean Journal of Clinical Pharmacy
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• v.7 no.1
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• pp.45-49
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• 1997

The effect of the light on the stability of 5-fluorouracil admixture was investigated. Four sets of 5-fluorouracil admixture were prepared using 50 mg/ml injection in $5\%$ dextrose solution in PVC bags and glass bottles: (1) 5-fluorouracil 1 mg/ml concentration in glass bottles, (2) 5-fluorouracil 1 mg/ml in PVC bags, (3) 5-fluorouracil 10 mg/ml in glass bottles, and (4) 5-fluorouracil 10 mg/ml in PVC bags. In each set, one group was protected from the light (control group) and the other group was exposed to the fluorescent light (study group). All admixtures were stored at room temperature for 72 hours. Also, 5-fluorouracil injections (50 mg/ml) were prepared in plastic syringes. Half of the samples of 50 mg/ml concentration were protected from the light (control group) and the other half were exposed to the fluorescent light (study group). These were stored at room temperature for 48 hours. After visual inspection, the pHs of each admixture were determined. The 5-fluorouracil concentrations were measured by high-performance liquid chromatography with UV detection, with 5-bromouracil as an internal standard. Over the study period, no visual changes were observed. The pHs of 5-fluorouracil admixtures were in the range of $8.2\~8.5$. The peak area ratios (5-FU/5-BrU) of 5-fluorouracil admixtures protected from the light were compared with those of the admixtures exposed to the light. There was no statistically significant difference between two groups during the study period (p>0.05). In conclusion, 5-fluorouracil admixtures in $5\%$ dextrose solution exposed to the light were stable for 72 hours.

• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.328-332
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• 1997

The ripe fruit of Hass avocado contains one of the highest elvels of cytochrome P-450 protein found in the plant kingdom. To determine whether wounded roots of avocado contain P-450 protein, the roots of avocado were wounded by slicing, and then allowed to incubate in sealed plastic bags, in 0.4M mannitol, and in the solution to make protoplast preparation containing cellulysin and macerase during the specified times. The microsomal proteins were extracted from the samples, separated by SDS-PAGE, and then subjected to Western blot analysis using polyclonal antibodies which are generated against the CYP71A1 protein. wounded roots in sealed bags produced CYP71A1 within 6 hours after cutting, and those in 0.4M mannitol did not produce CYP71A1 even after 72 hours, but those in the protoplast preparation by cellulysin and macerase induced and produced CYP71A was induced in only 24 hours. These results indicate that CYP 71A1 plays a role for wound healing for root tissue o avocado, and would-inducible P-450 protein was not detected in the mannitol solution by preventing a synthesis of ethylene in a liquid state, but the softening of tissues by cellulysin and macerase to make protoplast preparation was involved in an activation of CYP 71A1 even in the liquid state.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.427-432
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• 2009

This article deal with an overview of food waste treatment methods in Korea. Garbage trucks are operated manually by garbage workers who pick up the food wastes after food waste is placed in plastic bags by the road sides. However, there are a lot of problems such as, the smell from the split bags and the leachate, the loss of much energy and the complaints regarding the establishment new rubbish tips from the residents in the surrounding area. It also highlights our society's waste of resources. Although the new pneumatic waste transfer system or the dry method seem to have improved some of the environmental conditions, it still bears some problems, for example, the lack of reuse and recycling of resources and the economic problems. We have been analysed the advantages and disadvantages between the existing food waste system and the pneumatic waste transfer system. And the dry method and disposer were discussed. The results will indicate how the disposer can improve more than the existing systems and will provide the evidence to support.

• Archives of Plastic Surgery
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• v.35 no.5
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• pp.581-588
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• 2008

Purpose: It is generally accepted that anatomical structures of the soft tissue in Asian faces are quite different from those in Caucasian. It is presumed that these differences are due to collagen rich thick dermis and durable superficial musculo-apponeurotic system (SMAS) in Asian. We classified the aging lower eyelids and reviewed the operative procedures according to the types of aging lower eyelids in Asian. Methods: We compared preoperative and postoperative photos of 117 patients over 30 years of age, who underwent lower blepharoplasty at the Kyunghee Medical Center from January 2001 to April 2006. We classified the patients based on the degree of skin laxity, presence of nasojugal groove and malar bag, the extent of aging process. We also reviewed the operative procedures according to each type of classification. Results: We classified our patients into four types as following. Type I patients showed minimal skin-muscle excess confined to lower eyelids regardless of the facial line. For these patients, we performed only transcutaneous or transconjunctival blepharoplasty. In type II patients, nasojugal grooves were shown and skin- muscle laxity was limited to the medial side of imaginary vertical line at lateral margin of pupil. In these cases, we performed free fat graft or fat repositioning on nasojugal groove or fat removal and septal duplication confined to medial side. Type III patients displayed more advanced medial bulging and remarkable laxity over the lateral side, the same operation methods as those of type II were applied at the lateral side of the line. Type IV patients demonstrated extensive midfacial aging changes including malar bags and underwent superficial subciliary cheek lift. Conclusion: The lower eyelid aging of Asian is different from those of Caucasian. We think that our classification is useful in selection of appropriate operative procedure to address specific problems for Asian patients.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.425-431
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• 2009

Antimicrobial coating on chicken carcasses may reduce the effects of cross-contamination and improve product shelf-life and safety. Thyme oil was mixed at 0.5%(v/v) with a pre-gelatinized pea starch coating solution. The coating solution was spread on chicken breast meat after inoculation with selected spoilage and pathogenic bacteria. After inoculation, the chicken meats were packaged in plastic bags and stored at $4^{\circ}C$. During 12 day storage, total aerobic bacteria, lactic acid bacteria, and inoculated organisms were counted at 4 day intervals. Thyme oil treatments reduced the viability of Salmonella as well as the growth of Listeria and Pseudomonas by 2 log CFU/g, and appeared to eliminate inoculated Campylobacter during storage. The addition of thyme oil increased the viscosity of the pre-gelatinized pea starch solution. The results suggested that thyme oil inclusion in an edible starch coating may be a satisfactory delivery system to enhance the safety of processed fresh meat.