In this study, as part of the paradigm shift for manufacturing innovation, data from the multi-stage cold forging process was collected and based on this, a big data analysis technique was introduced to examine the possibility of quality prediction. In order for the analysis algorithm to be applied, the data collection infrastructure corresponding to the independent variable affecting the quality was built first. Similarly, an infrastructure for collecting data corresponding to the dependent variable was also built. In addition, a data set was created in the form of an independent variable-dependent variable, and the prediction accuracy of the quality prediction model according to the traditional statistical analysis and the tree-based regression model corresponding to the big data analysis technique was compared and analyzed. Lastly, the necessity of changing the manufacturing environment for the use of big data analysis in the manufacturing process was added.
The method of evaluating the forming limit of sheet metal is using the forming limit diagram(FLD), and the test method for measuring forming limit curve(FLC) is ISO standardized. On the other hand, in the case of metal bulk materials, it was confirmed that the forming limit was defined by using various predictive models based on the ductile fracture theory. However it did not show a constant forming limit (limit damage value) depending on the shape of the specimen. Therefore, a study was conducted on the derivation of the triaxial stress curve to predict the fracture of the material for various stress triaxiality, not the existing limit damage value.
The global trend is the application of heat-treated omission materials to reduce the manufacturing cost of automobile steering parts. Attempts have been made to apply heat-treated omission materials in domestic, but they are delayed due to concerns over rising cold forging process costs. For quantitative prediction of cold forging process cost, fatigue properties of forging die materials were evaluated. Based on this, the die life and cost were predicted quantitatively, and the manufacturing cost reduction of automobile steering parts using heat-treated material was found to be about 11%. Also, various methods to improve die life were additionally presented.
Forged part made of Cold heading quality wire materials are used for automotive brake systems. The cost reduction of forged products is a major issue because of the strict shape change. A series of studies were conducted to minimize the cost of EPB spindle process among brake parts. In order to reduce the material cost, heat treatment-abbreviated material was applied and the formability on the processes was verified by the ductile fracture theory. In addition, the causes of shape fixation and die life degradation were analyzed using the numerical simulation. The process cost has been minimized by re-designing process, changing the product shape, and the die material.
The dual effectiveness of Opuntia ficus indica extracts for browning inhibition and microbial inactivation on fresh-cut apples was investigated. Prepared apple slices were treated with 25, 50, 100, 200 mg/mL Opuntia ficus indica extracts, packaged in polyethylene bags, and stored for 10 days at 4, 21oC. Results indicate that Opuntia ficus indica extracts significantly (P < 0.05) inhibited the browning reaction of fresh-cut apples. This treatment also reduced peroxidase activities. The populations of Staphylococcus aureus significantly decreased with increasing extract concentration (p < 0.05). In particular, S. aureus was reduced to non-detectable levels after 2 days in 100 mg/mL treatment at 4oC and 21oC. Opuntia ficus indica extracts therefore have antibacterial and antibrowning effects. The results suggest that Opuntia ficus indica extracts could be useful as a natural food preservative.
Zingiber officinale Roscoe, commonly known as ginger, has long been used as a powerful health-promoting antioxidant that supports cellular health of the human body. The objective of this study was to compare the antioxidant and antimicrobial activities of the samples with aging and fermentation. Antioxidant activities of the samples were compared using total phenol, flavonoid contents, ABTS cation radical scavenging activity and DPPH radical scavenging activity. Antimicrobial activities were also examined using the paper disc method and minimum inhibitory concentration (MIC). Acidity of the fermented ginger (FG) with lactic acid bacteria showed a significantly higher value than that of the ginger (GG). The content of 6-gingerol, a bioactive component in ginger, decreased in all fermented gingers but 6-shogaol which is also one of the main valuable ingredients showed the increased content at ginger fermented with Streptococcus thermophilus and Lactobacillus acidphilus. Flavonoid contents of the FG and GG did not show significant differences. However, ABTS cation radical scavenging activity and DPPH radical scavenging activity were 10-30% increased in the samples with fermentation (p<0.05), respectively. The samples of the disc showed an inhibitory effect on growth of gram positive Staphylococcus aureus and Listeria monocytogenes. Zinger with fermentation showed higher antioxidant and antimicrobial activities. Thus, we conclude that aging and fermentation can be a helpful process to increase the functional effects of ginger.
We report the development of new anthocyanin-rich grain corn hybrid variety ‘Saekso 2’. The seed parent, HA3 and the pollen parent, HA4 was developed from breeding materials collected from China in 2008 and from Canada in 2000, respectively. The hybrid was made in the winter of 2010/2011 and evaluated in Hongcheon for 3 years. After evaluation, the selected variety was named ‘Saekso 2’ and was approved for a variety registration in 2017. Anthocyanin content of Saekso 2 in grain was 685 mg/100g and was much higher than that of Saeko 1(0mg/100g). Since regional tests was conducted in only Gangwon province, it is recommended only in that region for commercial cultivation. For the highest content of anthocyanin, it is best to harvest grains at around 45 days after silking. Saekso 2 is the first hybrid bred specifically for processing for high anthocyanin production.
This study was carried out to create new popcorn variety. ‘G-Popcorn’ was made by single crossing with two inbred lines, the seed parent, GP3, and the pollen parent, GP4. The hybrid was made in 2009 and selected in 2014 after investigating characteristics for three years from 2012 to 2014. ‘G-Popcorn’ was evaluated on 2 or 3 places in Gangwon-do for three years. ‘G-Popcorn’ showed higher lodging tolerance and popping volume in contrast to the check variety ‘Oryunpopcorn’. The plant height is 213cm indicating 5cm lower than that of ‘Oryunpopcorn’. Also, ration ear height of plant height of ‘G-Popcorn’ is 59%. The weight of 100 seeds was 15.5g, similar to that of ‘Oryunpopcorn’. The popping volume of ‘G-Popcorn’ was about 28.3㎤/g, higher than 25.0㎤/g of ‘Oryunpopcorn’. The yield of ‘G-Popcorn’ was 467kg/10a in regional yield trials for three years, which was 7% higher than that of ‘Oryunpopcorn’.
This study was carried out to create new waxy corn variety using anthocyanins germplasm including 13 ornamental maize stocks, purple corn and two parental lines of Mibaek2. First, we made anthocyanin husk population for sustainable breeding from 13 ornamental stocks for 6 years from 2001 and then crossed purple corn with a dark purple kernel in 2007. We crossed this hybrid with two parental lines of Mibaek2, a good edible quality waxy corn, in 2007/2008 dry season nursery for additional breeding in Thailand. The anthocyanin-rich waxy lines derived from these hybrids were self-fertilized seven times and made single cross hybrids until 2011. These hybrids were evaluated on 2 or 3 places in Gangwon-do for next two years. One selected elite hybrid was named Cheongchunchal and applied for registration of new waxy corn variety in March 2014. Total anthocyanins content is zero in Mibaek2, 737 in Miheugchal, 18,809 mg/kg in Cheongchunchal. This variety is meaningful as health food and high-value industrial material.
With the economy development, people have an increasing demand for meat and eggs. Hence the market demand for cereal crop keeps increasing. maize is the major crop to meet the conditions of market demand. As a part of the Golden Seed Project, we are planning to develop maize varieties for adaptation in Southern Asia, especially in India. This project was started at 2013 and has been collaborated with Nongwoo Bio Co. Our project is based on overseas maize breeding in Bangalore, India. At first year, we tested 40 maize hybrids to investigate adaptability, yield capacity, and growing characteristics. Planting materials for this test were developed and selected in Cambodia by researchers of Maize Research Institute. Growing performance is usually quite different by the growing area and seasons, but some of our materials have shown good adaptability and yield at dry season in Southern India. 13IN07 was selected by yield and grain color, 13IN39 was selected by yield and plant type. These two selected hybrids were applied to regional test controled by Indian Council of Agricultural Research in India. We will see how our hybrids adapt in various regions in India, assess how other tested hybrids perform in those regions, and compare each other. We may also expect one of the selected hybrids can be a candidate variety for some regions in India and we will continuously select good hybrids and develop new varieties in India.
Maize breeding is mainly divided by two steps; line development and hybrid selection. Line development is very important procedure to make good hybrids and this line development in Korea is fully depend upon conventional methods like pedigree selection, back-cross, etc. For development of pure line, we have to do self-pollination for at least seven cycles. This line development system is tedious, labor-intensive, and time-consuming procedure. Doubled Haploid technology for maize is a new system to develop inbred lines within short period and many maize research institutes in foreign advanced countries have been actively using this technology. Using Doubled Haploid technology, we can greatly reduce the period of line development and strengthen maize research ability in Korea. Key requisite for Doubled Haploid breeding is possession of inducer lines which can produce haploid when source population is crossed with them. Maize Research Institute in Gangwon Province secures the right of using inducer lines and is trying to introduce Doubled Haploid breeding in Korea. Doubled Haploid breeding system is as follows; crossing between population and inducer, separation haploid seeds from F1 seeds, chromosome doubling, doubled plant management, self-pollination, seed multiplication, and assessment. We expect our breeding capacity will be progressed by introduction of Doubled Haploid technology. When this technology comes to combine with marker assisted selection, we can increase competitiveness against global institutes.
학교 급식 식재료로 사용되는 농산물 중 잔류농약의 안전성을 평가하고자 서울시내 초, 중, 고등학교 110곳에서 316건의 시료를 수거하여 잔류농약을 분석하였다. 185종의 농약에 대해 GC-ECD, GC-NPD, GC-MSD 및 HPLC-UVD를 이용한 다종농약 다성분 분석법으로 잔류농약을 분석하였고, 분석결과 26건의 시료에서 농약이 검출되었고, 취나물과 들깻잎에서 각각 57.1, 55.6%의 높은 검출율을 나타내었다. 농약 성분별 검출빈도는 프로시미돈, 엔도설판, 아족시스트로빈의 순으로 높게 나타났으며, 2종 이상의 농약이 동시에 검출된 것은 3건이었다. 그리고 검출된 시료 중 잔류 허용기준을 초과한 시료는 6건이었으며 시금치, 취나물, 양배추에서 엔도설판, 깻잎에서는 디니코나졸과 카보후란, 고추에서는 에토프로포스가 잔류허용기준치를 초과하여 검출되었다. 위해성 평가결과 들깻잎에서 검출된 카보후란의 hazard index가 3.8%로 가장 높았으며, 다른 농산물들은 모두 2% 미만을 나타내어 위해도가 매우 낮은 것으로 조사 되었다. 따라서 서울지역 학교급식 식재료로 사용되는 농산물은 비교적 안전한 수준으로 농약관리가 이루어지는 것으로 판단되며, 지속적으로 농약의 안전한 사용을 위한 홍보와 교육이 이루어져야 할 것으로 여겨진다.
We are importing corn grains more than eight million tons every year, and self-sufficiency rate of corn is less than one percent. It is not easy to increase field corn production in Korea because of limited arable land. For this reason, many companies have been interesting overseas agriculture for corn production. But they don’t have enough suitable variety for the target area. Our objective is to develop field corn varieties for adaptation in Primorsky Krai which is the southeasternmost region of Russia. This project has been collaborated with Dr. Huk-Ha Lee in Seoul National Univ. and planted three times in Primorsky Krai since 2011. Planting materials for this project were developed in Maize Research Institute. 74 hybrids in 2011, 76 in 2012, and 80 in 2013 were planted for regional performance test. Primorsky Krai is a colder area and has less frost-free days than Korea. Several hybrids have shown good performance, but lots of materials developed in Korea could not fully ripened in 2011 because of late planting and early frost. In 2012, we mainly selected early flowering materials as well as picked materials from first year. The silking date of our materials was later than local commercial varieties, but some our hybrids had good characteristics and high yield. Among them, we picked two hybrids and planted them in Ussuriysk in Primorsky Krai for field demonstration test. We expect some of the selected hybrids can be candidate varieties for improvement of corn production at overseas agricultural production base.