• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.52 no.3
• /
• pp.259-263
• /
• 2007

Sowing time of barley after cultivation of rice has frequently been delayed because of rainfall or some other reasons by rice cultivation. Partial tillage direct grain seeder with eight row, which had been developed for rice sowing and showed many advantages in wet field, were tested for barley sowing. After flooding during $2{\sim}3days$, plots were designed to make wet condition. Three sowing methods were tested; high ridged broadcasting, plat drill seeding and partial tillage direct grain seeding. It were impossible to sow properly even in 27% of soil water content by high ridged broadcasting, plat drill seeding but could be possible to sow normally by partial tillage direct grain seeder in 42% of soil water content as good as in 27% of soil water content. Initial growth condition after sowing in plots of partial tillage direct grain seeder were normal even in plots sown in more than 50% of soil water content. No. of spike, which was $508/m^2$, in plot of partial tillage direct grain seeder sowed at 30% soil water content was better than plat drill seeding, $404/m^2$. Yield and yield components of plot of partial tillage direct grain seeder, were higher than plot sowed by plat drill seeder in same soil water content. Partial tillage direct grain seeding can be a good sowing way for barley especially in wet condition. However, parts of seeder have to be improved for barley sowing; 1) ridged width of partial tillage direct grain seeder should be $10{\sim}20cm$ wider than 10 cm, which is necessary for drainage during barley growing season in wet paddy field. 2) sowing width of partial tillage direct grain seeder was not same with one of drill seeder which was the best width for light interception and should be shorter than 30cm.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.29 no.3
• /
• pp.153-161
• /
• 2023

The worldwide effects of COVID-19 have led to a surge in online shopping and contactless services. The consumption pattern has caused the issues such as the environmental pollution together with the increase of plastic waste. Reducing the reliance on the petroleum based plastic use for the package and replacing it with environmentally friendly material are the simple ways in order to solve those problems. Paper is an eco-friendly product with high recyclability as the food packaging materials but has still poor barrier properties. A barrier coating on surface of the paper can be achieved with the proper packaging materials featuring water, gas and grease barrier. Polyethylene (PE) or polypropylene (PP) coatings which are generally laminated or coated to paper are widely used in food packaging applications to protect products from moisture and provide water or grease resistance. However, recycling of packaging containing PE or PP matrix is limited and costly because those films are difficult to degrade in the environment. This study investigated the recyclability of modified acrylic emulsion coating papers compared to PE and PP polymer matrixes as well as their mechanical and gas barrier properties. The results showed that PE or modified acrylic emulsion coated papers had better mechanical properties compared to the uncoated paper as a control. PE or PP coating papers showed strong oil resistance property, achieving a kit rating of 12. Those papers also had a significantly higher percentage of screen reject during the recycling process than modified acrylic coated paper which had a screen rejection rate of 6.25%. In addition an uncoated paper had similar value of a screen rejection rate. It may suggest that modified acrylic emulsion coating paper can be more easily recycled than PE or PP coating papers. The overall results of the study found that modified acrylic emulsion coating paper would be a viable alternative to suggest a possible solution to an environmental problem as well as enhancing the weak mechanical and poor gas barrier properties of the paper against moisture.

• Journal of Bio-Environment Control
• /
• v.23 no.2
• /
• pp.88-94
• /
• 2014

This study was carried out to survey the early growth characteristics of Ligularia fischeri, plants of half-shaded grounds, primarily used as functional wild edible greens and examine its shading treatment to transplant seedling. The shading treatment was regulated with the shading level(full sunlight, 35%, 50%, 75%, and 95% of full sunlight). According to the experiment, the height was the highest under 75% of shading (17.3 cm), and root diameter was the highest under full sunlight (2.13 mm). It was found that fresh weight (leaf, shoot, root and whole) was the highest (1.784 g, 1.330 g, 0.791 g, 3.905 g respectively ) under 50% of shading. In case of dry weight, leaf, shoot and whole dry weight were surveyed the highest under 35% of shading, and root dry weight was the highest under full sunlight. It was found that S/R ratio and moisture contents (leaf, shoot, root and whole) were the highest under 95% of shading. Leaf area was the highest under 50% of shading ($39.3cm^2$) and the higher shading level, the higher SLA and LAR. It was surveyed that the higher shading level, the thinner leaf thickness. In case of root characteristics, it was showed that the relatively high height growth under 35%~75% of shading, excepting 95% of shading. As a result of surveying the whole experiment, it is concluded that the early growth of L. fischeri is more effective in producing it under 50% of shading.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.26 no.4
• /
• pp.249-256
• /
• 2006

The object of this experiment was to suggest the optimum autumn sown small forage crops as next forage crops harvested maize in Daejeon area. The field trials was conducted from 2002 to 2004 at Chungnam National University in order to evaluate the dry matter yield and qualities of the autumn sown small forage crops. The experiment was consisted of split plots (main plot : forage crops as rye, barley and wheat, and sub plot 4 harvest stages as boot, heading, milk and dough) design with three replications. The average DM yield for 2 years of rye was higher than that of other forage crops (p<0.01). As stages proceed, the DM yield tended to increase in all forage crops (p<0.01). In chemical composition, they had a difference on forage crops and stages. The crude protein (CP) was higher in barley (p<0.01), but fibrous contents such as NDF, ADF, cellulose and lignin were lower in wheat than in the other forage crops (p<0.01). In Daejeon area, although barley and wheat at milk and dough stages were observed with maximum yield and high quality as autumn sown forage crops, due to late harvesting periods, it is difficult to utilize them as previous forage crops seeded in maize. Based on the result mentioned above, it is concluded that rye harvested at boot to heading stages is the most suitable fur autumn sown small forage crops in Daejeon area. Meanwhile, in order to have the option of nutritional value in wheat and barley, they need to be supplied early maturing and high-yield variety of wheat and barley.

• Journal of Food Hygiene and Safety
• /
• v.19 no.2
• /
• pp.60-65
• /
• 2004

120 samples of ready-to-eat salad product were purchased at department stores, marts and family restaurants in metro area. Coliform bacteria and food borne pathogenic bacteria were isolated from these samples. In 73 samples among the 120 salad product samples, coliform bacteria and food borne pathogenic bacteria were detected by 60.8％ of isolated rate. Salad were classified into organic and non-organic salad. According to a salad type, salad were classified into vegetable salad and mixed vegetable salad with fried chicken and extra food. According to a packing type, packed salad product and salad-bar product were classified. After the classification, the results of each cases were compared. There is no statistical relation between cultivation or packing methods and contaminated bacteria. But the incidence number of microbial strains was significantly different between vegetable salad and mixed vegetable salad(p＜0.005). In vegetable salad, more various strains were detected. E. coli was isolated in 10 cases among the 90 cases in non-organic vegetable and in 7 cases among the 30 cases in organic salad. Food borne pathogenic bacteria were isolated in non-organic vegetable salad product. Staphylococcus aureus was isolated in 4 cases of vegetable salad product and Salmonella spp. isolated in 1 case. After 5 times examination of each 4 market products, the total number of aerobic bacteria was average 4.8$\pm$0.19 log cfu/g. One sample from this product, saline and a detergent for vegetable were used for 3 minutes to notice the effect. As a result, when saline was used 5 times and detergent for vegetable was used 1 time, bacterial contamination was decreased up to 95.5％.

• Korean Journal of Soil Science and Fertilizer
• /
• v.1 no.1
• /
• pp.27-41
• /
• 1968

In order to clarify the effect of various forms or phosphate on the production of paddy in Korea and to find out the superiority of any form, a number of field and pot experiments involving various phosphate fertilizers were carried out in addition to conducting one each of sand culture and soil culture pot experiments in 1963 and 1964. The results of these studies are summarized as follows: 1. In sand culture experiment, the best effect of a phosphate fertilizer was obtained with the mono-calcium phosphate which is soluble in water, followed by citric acid soluble phosphate such as fused phosphate and di-calicum phosphate. However, in the pot culture and field experiments, fused phosphate had shown it's superiority than triple superphosphate which contains water soluble form of phosphate followed by hypo phosphate, roasted phosphate, compound fertilizer, and slag phosphate. The effect of rock phosphate was the least in most cases. 2. The superiority of fused phosphate to triple super phosphate in soil culture was supposed to be: a) The fused phosphate can neutralize the soil acidity. b) The fused phosphate can supply magnesium and magnesium lead to the balanced conditions of exchangeable bases in soils. c) The magnesium in the fused phosphate helps the transportation of phosphate, and regulate the absorption of the element.

• Proceedings of the Korean Society for Agricultural Machinery Conference
• /
• 2017.04a
• /
• pp.65-65
• /
• 2017

밭작물 중 양파와 마늘은 높은 노동투하시간, 노임의 상승, 복잡한 수거 과정 등으로 최근 재배면적이 감소하는 추세이다. 밭농업 활성화 방안으로 생산비 절감과 작업 속도 향상을 위한 수확기계 개발 연구로 줄기절단기가 개발되었다. 이 연구는 줄기절단기 예취날의 설치각이 절단부하에 미치는 영향을 분립체 해석 기법으로 분석하고자 하였다. 실험에 사용한 시뮬레이션은 EDEM으로 인장탄성계수, 전단탄성 계수, 중첩길이, 입자 반경 및 질량, 상대속도를 이용하여 충돌시 힘을 해석하고 인장 및 전단강도, 한계, 결합 길이를 통해 입자간 결합을 설정할 수 있다. 시제품으로 설계된 줄기절단기의 치수를 활용하여 프로그램 상에서 줄기 절단 시뮬레이션을 진행하여 절단부하 결과를 얻도록 하였고 칼날 설치각을 30도, 45도, 60도로 변경하여 각각의 부하를 분석하여 경향성을 파악하고자 하였다. 실험에서 사용한 프로그램은 EDEM 2.7.1 Academic Research 버전이며 시뮬레이션을 진행한 PC의 사양은 Intel(R) $Core^{TM}$ i7-4790 CPU @ 3.60GHz, Memory 16.0GB이다. 줄기 절단 시뮬레이션에 적용시킨 줄기 모델은 마늘의 조건을 적용시켜 직경 1mm의 입자로 이루어진 지름 12mm, 높이 214mm의 원통형 모델이며 60.32N의 최대절단력을 가지고 있다. 줄기절단기는 2개의 회전날을 가지고 있으나 좌우대칭을 적용하여 절반에 대한 해석으로 하나의 회전날로 절단을 하도록 줄기 모델은 4조로 하여 3열을 140mm 간격으로 위치시켰다. 줄기절단기의 칼날은 반경 350mm로 회전하며 진행속도는 1.65m/s, 회전속도는 1680rpm으로 작업하도록 하였다. 시뮬레이션은 0.5초의 시간에 대해 해석하도록 하였으며 0.003초 간격으로 칼날에 가해지는 힘을 구하여 저장하도록 하였다. 시뮬레이션 해석시간은 약 116시간이었으며 설치각별 시간에 따른 칼날에 가해지는 압축력 값과 그래프를 얻을 수 있었다. 대부분의 시간에서 절단이 이루어지지 않으므로 0의 값을 나타내었으며 절단이 이루어지는 시점에 절단부하가 나타났다. 결과 해석을 위해 그래프의 피크 값들을 이용하였으며 그 중 상위 6개의 값으로 분석하였다. 30도, 45도, 60도의 설치각에 따른 절단부하의 평균 값은 각각 105.4N, 160.5N, 215.9N으로 나타났다. 설치각에 따른 절단부하의 경향성은 유의수준은 3.93%로 각각의 차이가 유의미하게 나타났으며 상관계수는 0.489로 증가하는 경향이 보였다. 그러나 $R^2$는 0.2394로 낮은 값을 보여 데이터 처리 방법의 개선과 적절한 회귀 모델의 적용이 필요하다. 향후 포장시험을 진행하고 복합적으로 분석하여 경향성을 자세히 분석하고자 한다.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.27 no.3
• /
• pp.151-154
• /
• 2007

This experiment was conducted to compare the agronomic characteristics and productivity of introduced crimson clover cultivars at paddy field of Naju(Jeollanam-Do Agricultural Research and Extension) from 2004 to 2006. The crimson clover cultivars used in this study were 4 varieties('Oregon com.' 'Tibbee', 'Contea', 'Linkarus') The fastest flowering variety was chinese milk vetch, while 'Linkarus' was the latest one as of as 5th May. The average dry matter(DM) content was 24.3% and crude protein(CP) content was 14.9%. 'Oregon com.' showed the highest CP content of 18.3% among crimson clover and Chinese milk vetch showed the highest CP content by 19.3%. Average acid detergent fiber(ADF), neutral detergent fiber(NDF) and total digestible nutrient(TDN) content were 35.1%, 45.3% and 58.9%, respectively. With by the winter hardness the productivity of crimson clover cultivars were severely various. Linkarus showed the highest DM yield with 6,986kg/ha but the DM yield of 'Tibbee' and 'Oregon com.' was low by 3,639 kg/ha and 1,980kg/ha, respectively. The results of this experiments indicated that the productivity of crimson clover cultivar varied from winter hardness, therefore we will consider the winter hardness as major factor when introducing crimson clover cultivars into Korea. According to the results obtained from this study, it is suggested that 'Linkarus' would be recommendable for fall sown crimson clover for dry matter production.

• The Korean Journal of Pesticide Science
• /
• v.19 no.4
• /
• pp.424-427
• /
• 2015

Damping-off is a critical disease on ginseng seedling, which caused by the fungal pathogen Rhizoctonia solani. The disease has been prevented by tolclofos-methyl for the last 20 years. However, the tolclofos-methyl usually detected on the harvested roots of 6-year-old ginseng. Herein, we tried to select an alternative pesticide which not only must be safe but also efficiently inhibits the fungal pathogen. Four fungicides (fludioxonil, flutolanil, pencycuron, and thifluzamide) were applied to their inhibition efficacy against the pathogen. In in vitro test, fludioxonil treatment showed 80% inhibition activity for 25 days. Thifluzamide and flutolanil showed the activity for 10 days. Pencycuron showed for 1 days. In addition, the fludioxonil was more effective to control the pathogen comparing to other three fungicides in field. The incidence of damping-off was reduced to 71% by fludioxonil treatment. The level of the fungicide residue in seedling was 0.44 mg/kg, which value will be a negligible level in final products after 5 years. Consequently, the fludioxonil is a conceivable alternative for tolclofos-methyl to cope with R. solani.

• Korean Journal of Weed Science
• /
• v.5 no.2
• /
• pp.143-148
• /
• 1985

Water hyacinth, unused and tropical plant was examined in order to know the feasibility of application for purification of municipal drainage and industrial wastewater. This plant was effective to remove the COD from wastewater, although its removal ability was dependent on the organic sources. The effects of pH, NaCl concentration, water temperature and shading condition on the growth of water hyacinth were investigated. The optimum ranges of pH were weak acid- neutral, of water temperature were 17-$21^{\circ}C$, and unshading condition was better. The rapid propagation of this plant was also observed during hot summer season.