• Journal of Food Hygiene and Safety
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• v.28 no.1
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• pp.7-12
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• 2013

This study presents the influence on growth properties determined using a novel predictive growth model of wild-type Salmonella spp. KSC 101 by variations in the temperature and time during cut packaging in cold, uncooked pork meat. The experiment performed for model development included an arrangement of different temperatures ($0^{\circ}C$, $5^{\circ}C$, $10^{\circ}C$, $15^{\circ}C$, and $20^{\circ}C$) and time durations (0, 1, 2, and 3 hours) that reflect actual pork-cut and packaging processes. No growth was observed at $0^{\circ}C$ and $5^{\circ}C$, whereas some growth was observed at $10^{\circ}C$, $15^{\circ}C$, and $20^{\circ}C$, with a mean increase of only 0.34 log CFU/g. The growth observed at $20^{\circ}C$ was more robust than that observed at $15^{\circ}C$, but the difference was not statistically significant (p > 0.05). However, compared with PMP (Pathogen Modeling Program), the wild-type Salmonella spp. KSC 101 showed a more rapid growth. We used the Gompertz 4 parameter equation as the primary model, and the exponential decay formula as the secondary model. The estimated $R^2$ values were 0.99 or higher. The developed model was evaluated by comparison of the experimental and predictive values, and the values were in agreement with the ${\pm}0.5$ log CFU/g, although the RMSE (Root mean square error) value was 0.103, which indicates a slight overestimation. Therefore, we suggest that the developed predictive growth model would be useful as a tool for evaluating sanitation criteria in pork cut-packaging processes.

• Economic and Environmental Geology
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• v.46 no.4
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• pp.291-300
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• 2013

The potential mineral resources in North Korea are magnesite, limestone, coal, graphite, iron, gold, silver, lead, and zinc. North Korea is mainly exporting coal and iron to China(70%) and EU countries. Gold ore reserves(or resources) in North Korea are about 2,000 tons and annual production is 2 tons based on metal. Major gold mines are Sooan, Holdong, and Daeyoodong mines and six smelters are operating. Fe ore reserves (or resources) are 4.3 billion tons and annual production is about 5 million tons based on 63.5% Fe. Major iron mines are Moosan, Leewon, Eunryul, Shinwon, and Jaeryong and 7 smelters are operating. Pb and Zn ore reserves(or resources) are Pb 470,000 tons and Zn 15 million tons, and annual productions are about Pb 26,000 tons and Zn 50,000 tons based on metal respectively. Major Pb-Zn mines are Gumdock and Seongcheon mines. Magnesite ore reserves(or resources) are 2.8 billion tons (95% MgO) and annual production is about 150,000 tons. Major magnesite mines are Ryongyang, Daeheung Youth and Ssangryong mines, and 5 magnesium refractory factories are operating. Apatite ore reserves(or resources) are 340 million tons(30% $P_2O_5$) and annual production is about 300,000 tons(crude ore). Major apatite mines are Daedaeri, Dongam and Poongnyen mines. Coal is established as an important strategic fuel mineral resources and is a major energy source in North Korea. Coal ore reserves(or resources) are 18.6 billion tons and annual production is about 20 million tons. The main coal fields is located in southern Pyongan and the Jigdong mine is the biggest in North Korea.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.69-76
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• 2015

BACKGROUND: Contamination of soils by heavy metals is the serious environmental problem. In particular, industrial processing is one of the main sources of heavy metal contamination. The objective of this study was to investigate the distribution characteristics of heavy metals in soils collected from industrial complex. METHODS AND RESULTS: In this study, the soil contamination and enrichment factor (EF) of heavy metals were investigated in three national industrial complexes such as Yeosu, Ulsan and Sihwa Banwal industrial complexes. The target heavy metals includes Cd, Cu, As, Hg, Pb, Cr, Zn, and Ni. The results showed that the contents of Cd, Hg, Pb, Zn and Ni in Yeosu and the contents of Cu, As and Cr in Sihwa Banwal were higher than in any other industrial complex. The results of principal component analysis(PCA) in Yeosu, Ulsan and Sihwa Banwal complex could be explained up to approximately 81.4, 69.1 and 70.9% by two factor, respectively. Enrichment factors of Cd, Pb and Zn in all the investigated industrial complexes were above 1.0 that was the value judged to be a high contamination. And EF of Cr was above 1.0 in Sihwa Banwal complex. EF of Zn in all sites was generally high from the other heavy metals. CONCLUSION: Therefore, soils maybe significantly affected by heavy metals (especially, Cd, Pb and Zn) present in the emissions from industrial complexes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.12
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• pp.1757-1763
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• 2011

The physico-chemical properties of broccoli sprouts cultivated in a plant factory system with different lighting conditions were investigated. We reported that there were significant differences among the chemical and nutritional properties of the broccoli sprouts grown under different light sources. Two kinds of sugars (glucose and fructose) were detected in the plants. The amount of glucose was 2.94~3.12% and that of fructose was 1.54~2.04%. Total chlorophyll was $1,157{\pm}0.004$ mg% and chlorophyll-a $777{\pm}0.01$ mg%. All over the test materials, 2 kinds of organic acids (citric acid and malic acid) were detected. The level of citric acid was 908~1,136 mg% and its highest level was under the (Blue LED) light source. The level of malic acid was 514~834 mg% and its highest level was under the (Red LED) light source. Seven different minerals were also analyzed. The amount of K was 518 mg% and its amount was significantly higher than that of Mg or Na. There were also negligible amounts of Zn, Fe and Cu. The amounts of vitamin A, C and E under the Red LED were, $860.62{\pm}0.02\;{\mu}gRE$, $134.570{\pm}0.14$ mg% and $1.44{\pm}0.1$ IU. The amounts under the Blue LED were, $432.48{\pm}0.05\;{\mu}gRE$, $137.05{\pm}0.1$ mg% and $1.11{\pm}0.12$ IU. The amounts under both Red and Blue LEDs were, $667.33{\pm}0.11\;{\mu}gRE$, $118.50{\pm}0.09$ mg% and $1.47{\pm}0.1$ IU. And finally, the amounts under a White LED were, $640.25{\pm}0.08\;{\mu}gRE$, $119.87{\pm}0.07$ mg% and $1.31{\pm}0.15$ IU. In this study, significant changes were shown in the chemical and nutritional properties of the broccoli sprouts. These findings indicate that LED light sources stimulated germination of the plants.

• Journal of Korean Society of Forest Science
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• v.48 no.1
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• pp.40-50
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• 1980

This research was carried out to examine the substitutional feasibility of low-priced materials produced in waste of forest instead of wheat flour which is extended for plywood adhesives. Wheat, pine bark, wood flour and pine foliage of coniferous trees or poplar foliage of hardwood species were selected and pulverized into 60-100 mesh minute powder after they were dried at $100-105^{\circ}C$ during 24 hours in the drying oven. The prepared particles as above were added to urea formaldehyde resin, urea-melamine copolymer resin and water soluble phenol formaldehyde resin in the ratio of 10, 20, 30 and 50%. After plywoods were processed by the above extending ratios, shear strength of extended plywoods were analyzed and discussed. The results obtained at this study were summarised as follows; 1. In the case of urea formaldehyde resin, both dry and wet shear strength of plywoods extended by wheat flour were shown the highest value. 2. Dry shear strength of urea-melamine copolymer resin was better than that of urea formaldehyde resin on the whole, while plywoods extended by wheat flour were shown excellent results. 3. Among 10% and 20% extensions of urea-melamine copolymer resin, the best results were shown by poplar leaves powder, wheat powder and wood flour. They had no significant difference statistically. 4. In the case of water soluble phenol formaldehyde resin, although dry shear strength of pine leaves powder was higher than that of wheat flour in the ratio of 10%, there was no significant difference between them in the ratio of 10 and 20%. 5. Among 20, 30 and 50% extensions of water soluble phenol formaldehyde resin, wet shear strength of wood flour and bark powder was higher than that of wheat flour. Wet shear strength of wood flour in the ratio of 10% was shown the same tendency as above.

• Proceedings of the EASDL Conference
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• 2008.10a
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• pp.15-29
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• 2008

"떡"을 대표로 하는 중국 밀 문화는 선사시기의 야생 식물 재배는 역사상의 가공과 이용으로부터 현대 사회의 정밀 가공, 더 깊은 가공의 광범위한 이용에 이르기까지 수천 년의 긴 역사과정을 거쳤다. 그러나 20세기말 이전까지만 해도 밀가루는 중국 사람의 주식 원료 구성에서 그다지 중요하지 않은 위치에 있었다. 하지만 분명해야 할 것은 어떤 종류의 곡물이 한 민족의 주식 원료 구성에서의 높고 낮은 비중이 결코 간단하게 그 사회 의미와 문화가치의 높고 낮음과는 동일시할 수 없다. 중국 사람의 밀 식용 역사가 바로 하나의 전형적인 사례이다. 선진(先秦)시기, 밀의 재배와 식용은 주로 식량 공급이 줄곧 긴장된 상태에 처해있는 각 정권의 "接濟靑黃"(구제식량)하는 전략적 물자였다. 그러나 선진(先秦)시기에서 밀은 경제가치가 아주 높은 곡물은 아니었다. 그 원인은 밀의 무(畝)생산량이 상대적으로 낮을 뿐만 아니라 종자의 수요량도 상대적으로 크기 때문이다. 묵은 곡식은 다 사용되고 새 곡식이 무르익지 않은 공백기에 있는(청황불접) 시기에 전략적 곡식의 사회와 정치 의미 외에 강한 적응성, 광범위한 분포와 낮은 단가가 또한 밀의 상대적 장점으로 될 수 있다. 밀의 경제와 문화가치는 주로 한대(漢代)이후 차츰 드러났다. 혁명적인 변화는 바로 가루 음식의 섭취와 계속적인 확대이다. 밀을 가루로 내어 식용한 후 차츰 기타 곡물의 편의식품 전통 공간을 대체하였고, 한대(漢代)의 딤섬류 식품 "한구(寒具)(고대에 곡물가루 튀김 음식물 현재의 타래떡 등)"에 사용되는 재료도 거의 밀가루를 사용하였다. 오늘날 중국 사람이 자랑으로 여기는 전통식품인 국수, 만두, 혼돈(餛飩), 포자(包子), 소맥(燒麥), 떡, 찐빵(饅頭), 고(糕) 및 공업화 식품인 과자, 빵, 라면, 햄버거 등은 모두 밀가루를 기본 원료로 사용하고 있다. 나아가서 더욱 정밀하고, 다양한 딤섬 종류도 밀가루를 기본 원료로 한 주요 무대이다. 20세기말 이후 밀 소비 인구가 계속 확대되는 추세였으며 높은 소비량은 밀의 재배 면적 확대와 재배지역 확장을 결정하였다. 밀 소비량은 중국 사람의 주식 원료 소비에서 이미 근근이 벼 뒤를 잇는 지위에 올랐다. 통계 자료에 따르면 1949년 중국 밀 면적은 2,185만 헥타르로, 전국 식량 작물 총 면적의 19.6%, 총 생산량 1,380만 톤으로 전국 식량 작물 총 생산량의 12.2%에 달한다. 1980년에 이르러 면적은 2,884만 헥타르로, 총 생산량은 5,416만 톤에 달하였으며, 각각 식량작물 총면적의 24.8%, 총 생산량의 17.0%를 차지하였다. 1981이후 중국 밀 생산량은 또한, 새로운 발전을 가졌으며, 주로 단위 면적 생산량이 비교적 크게 증가되었고 총 생산량도 큰 폭으로 증가되었다. 1981~1985년과 1976~1980년의 5년 평균치를 비교한 결과 재배 면적은 같았으나(단지 0.2%만 증가), 단위 면적당 생산량 및 총 생산량은 46% 증가하였으며, 연평균 증가율이 9.2%에 달하여 50년 이래에 증가 속도가 가장 빠른 시기였다. 비록 지금 중국인의 "배부르게 먹기"문제는 이미 기본적으로 해결되었으나 장기적으로 "배부르게 먹기"의 물질적 보장은 여전히 취약하다. 농사가 가능한 경지면적의 급속한 격감으로 단위 면적당 생산량의 압력을 증가되었다. 국가 표준에 따르면 품질이 좋은 밀은 "탄력이 강한 고품질 밀"과 "탄력이 약한 고품질 밀" 두 가지로 구분된다. 지금 중국 시장의 추세를 보면 밀 품종의 선택에서 주로 탄력이 강한 고품질 밀을 선택하는데 즉 글루텐량이 높고 탄력이 강하며 품질이 좋은 전문 용도에 사용되는 밀을 선택한다. 탄력이 강한 고품질 밀은 주로 빵, 라면, 만두 등 밀가루 탄력을 요구하는 음식을 만드는데 사용된다. 그 중에서 모든 빵은 탄력이 강한 고품질 밀을 사용하고 밀에 대한 품질 요구도 또한 높다. 빵가루의 품질을 높이기 위하여 일부 전문 밀가루 생산 공장에서는 국산 고품질 밀에 수입 고품질 밀을 첨가하여 사용한다. 만두가루를 가공할 경우도 고품질 밀을 첨가하여 밀가루의 품질을 높이고 음식을 맛을 증가한다. 일부 품질이 떨어진 밀에 대하여 고품질 밀을 첨가하여 내부의 품질을 개선하고 찐빵이나 기타 밀가루 음식으로 가공한다. 예를 들면 중국 동북 지역에서는 고품질 밀과 봄밀을 섞어 밀가루의 봄밀의 품질을 개선한다. 총괄적으로 밀에 대한 욕구는 계속 장기적으로 벼에 버금가는 위치를 유지할 것이며 고품질 밀에 대한 욕구는 더욱 강한 추세로 발전할 것이다.

• Korean Chemical Engineering Research
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• v.51 no.2
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• pp.272-278
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• 2013

The hybrid system composed of a photocatalytic reactor and a biofilter was operated under various operating conditions in order to treat malodorous waste air containing ammonia which is a major air pollutant emitted from composting factories and many publicly owned treatment works. Total ammonia removal efficiency of the hybrid system was maintained to be ca. 80% even though its inlet loads were increased at a higher operating stage according to an operating schedule of the hybrid system. The ammonia removal efficiency of photocatalytic reactor was decreased from 65% to 22% as ammonia inlet loads to photocatalytic reactor were increased. In spite of same inlet loads of ammonia to the photocatalytic reactor, the ammonia removal efficiency of photocatalytic reactor with lower ammonia concentration of fed-waste air was higher than that with higher ammonia concentration of fed-waste air. To the contrary, during the first half of the hybrid system operation the ammonia removal efficiency of a biofilter was quite suppressed while, despite of increased ammonia inlet loads, the ammonia removal efficiency of the biofilter was continuously increased to 78% and reached the ammonia removal efficiency similar to what Lee et al. attained. The maximum ammonia elimination capacity of the photocatalytic reactor was observed to be ca. 16 g-N/$m^3$/h. In an incipient stage of hybrid system run, the ammonia elimination capacity of the biofilter showed little sensitivity against ammonia inlet loads to the hybrid system. However, in the 2nd half of its run, the ammonia elimination capacity of the biofilter was increased abruptly in case of high ammonia inlet loads to the hybrid system. In 6th stage of hybrid system run, total ammonia inlet load attained at ca. 80 g-N/$m^3$/h corresponding to 16 g-N/$m^3$/h of ammonia elimination capacity of the photocatalytic reactor. Then, the remaining ammonia inlet load to the 2nd and main process of the biofilter and its elimination capacity was expected and shown to be ca 64 g-N/$m^3$/h and ca 48 g-N/$m^3$/h, respectively. The ammonia elimination capacity of the biofilter was close to 1,200 g-N/$m^3$/day of the maximum elimination capacity of the investigation performed by Kim et al.

• Korean Journal of Agricultural Science
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• v.18 no.1
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• pp.74-79
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• 1991

In order to use of new organic matter source, soil samples collected from paddy, upland and orchard treated with kraft and paper board mill sludge were analysed comparing with non-treated soil in view of some soil properties, soil microorganisms and soil enzyme activities. Also, the value of fertilizer was estimated with kraft and paper board mill sludge. 1. Paper mill sludge showed more than 55% of organic matter content, and higher total nitrogen and phosphorus, and CEC. 2. Soils treated with kraft sludge were higher contents than non-treated 2.5-3 for organic matter, 1.5-2 for total-nitrogen, 2 for $NO_3$-N, 1.5 for phosphorus and 1.4 times for CEC. Also, 12-1.9 for bacteria and 3 times for fungi, and 1.4-1.5 of cellulase, 1.5-1.8 of phosphatase and 1.5-1.8 times of urease activities. 3. Organic matter contents, number of fungi, and activities of cellulase and phosphatase in soil treated with paper board sludge were 1.4-22, 2.4, 1.5-1.6 and 1.3-1.4 times higher than non-treated soil, respectively. 4. Paper mill sludge was evaluated as a good organic matter source to increase of soil organic matter, CEC, inorganic components, soil microbes and enzyme activities.

• Korean Journal of Environmental Agriculture
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• v.36 no.3
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• pp.193-200
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• 2017

BACKGROUND: Plant growth under smart greenhouse (that is plant factory system) conditions of an artificial light type is significantly depending on the artificial light sources such as a fluorescent lamps or Light-Emitting Diodes (LEDs) with specific spectral wavelengths regardless of the outside environmental changes. In this experiment, characteristics on the growth and compound synthesis of kale seedlings affected by light qualities and intensities provided by LEDs were mentioned. METHODS AND RESULTS: The kale seedlings which developed 3~4 true leaves were exposed by fluorescent lamps or LEDs lights of red (R), blue+white (BW), blue+red (BR) with 50 (L) or $100(H){\mu}mol/m^2/s^1$ photosynthetic photon flux (PPF) under hydroponic culture system of deep flow technique for 50 days. Shoot fresh weight increased under the RH, BWH, and BRH treatments with higher PPF. Shoot elongation of the seedlings decreased, and polyphenol synthesis promoted by the higher light intensity conditions. Sugar synthesis in the leaves was above 2 times greater under the RH treatment of monochromic red light quality with $100{\mu}mol/m^2/s^1\;PPF$ than $50{\mu}mol/m^2/s^1\;PPF$. CONCLUSION: The results show that the control of light quality and intensity in the smart greenhouse conditions with artificial lights significantly affects the growth and compound synthesis in the fresh kale leaves with higher culture efficiency compared to the conventional soil culture under greenhouse or field conditions. Researches on the optimum light intensities of the LEDs with special spectral wavelengths are necessary for maximum growth and metabolism in the seedlings.

• Journal of Wetlands Research
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• v.17 no.1
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• pp.45-52
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• 2015

We obtained the following results from investigation on vegetation damage from 5 to 6 August, 2013, about one year after an accident that hydrofluoric acid leaked from a chemical maker, Hube Globe in Gumi. Pinus densiflora and Pinus strobus showed very severe damage. Ginko biloba, Quercus acutissima, Pinus rigida, Salix glandulosa, Hibiscus syriacus, and Lagerstroemia indica showed severe damage. Quercus variabilis, Lespedeza cyrtobotrya, and Miscanthus sinensis showed moderate damage. Quercus aliena, Smilax china, Arundidinella hirta, Ailanthus altissima, Robinia pseudoacacia, and Paulowinia coreana showed slight damage. We did not find any plants without leaf damage around there. This result means that fluoride damage still persists in this area as was known that fluoride remains for a long time in air, soil and water and exerts negative effects at all levels of an ecosystem. In addition, fluoride content contained in plant leaf depended on the distance from a fertilizer producing factory and vegetation damage tended to proportionate to the concentration in the Yeocheon industrial complex. In these respects, a measure for removal or detoxification of the remaining fluoride is urgently required around the hydrofluoric acid leak spot. Fertilizing of dolomite containing Ca and Mg, which can trap fluoride, was prepared as one of the restoration plans. In addition, phosphate fertilizing was added in order to enhance soil ameliorating effects. Furthermore, we recommend the introduction of tolerant plants as the second measure to mitigate fluoride damage. As the tolerant plants to make a new forest by replacing trees died due to hydrofluoric acid gas damage, we recommended Q. aliena and S. china, A. hirta, etc. were recommended as plant species to add mantle vegetation to the forest margin to ensure stable interior environment of the forest.